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
;
79 * Copy string from src to dst and enforce null terminated byte.
82 void lttng_ctl_copy_string(char *dst
, const char *src
, size_t len
)
85 strncpy(dst
, src
, len
);
86 /* Enforce the NULL terminated byte */
94 * Copy domain to lttcomm_session_msg domain.
96 * If domain is unknown, default domain will be the kernel.
99 void lttng_ctl_copy_lttng_domain(struct lttng_domain
*dst
,
100 struct lttng_domain
*src
)
104 case LTTNG_DOMAIN_KERNEL
:
105 case LTTNG_DOMAIN_UST
:
106 case LTTNG_DOMAIN_JUL
:
107 memcpy(dst
, src
, sizeof(struct lttng_domain
));
110 memset(dst
, 0, sizeof(struct lttng_domain
));
117 * Send lttcomm_session_msg to the session daemon.
119 * On success, returns the number of bytes sent (>=0)
120 * On error, returns -1
122 static int send_session_msg(struct lttcomm_session_msg
*lsm
)
127 ret
= -LTTNG_ERR_NO_SESSIOND
;
131 DBG("LSM cmd type : %d", lsm
->cmd_type
);
133 ret
= lttcomm_send_creds_unix_sock(sessiond_socket
, lsm
,
134 sizeof(struct lttcomm_session_msg
));
136 ret
= -LTTNG_ERR_FATAL
;
144 * Send var len data to the session daemon.
146 * On success, returns the number of bytes sent (>=0)
147 * On error, returns -1
149 static int send_session_varlen(void *data
, size_t len
)
154 ret
= -LTTNG_ERR_NO_SESSIOND
;
163 ret
= lttcomm_send_unix_sock(sessiond_socket
, data
, len
);
165 ret
= -LTTNG_ERR_FATAL
;
173 * Receive data from the sessiond socket.
175 * On success, returns the number of bytes received (>=0)
176 * On error, returns -1 (recvmsg() error) or -ENOTCONN
178 static int recv_data_sessiond(void *buf
, size_t len
)
183 ret
= -LTTNG_ERR_NO_SESSIOND
;
187 ret
= lttcomm_recv_unix_sock(sessiond_socket
, buf
, len
);
189 ret
= -LTTNG_ERR_FATAL
;
197 * Check if we are in the specified group.
199 * If yes return 1, else return -1.
202 int lttng_check_tracing_group(void)
204 struct group
*grp_tracing
; /* no free(). See getgrnam(3) */
206 int grp_list_size
, grp_id
, i
;
208 const char *grp_name
= tracing_group
;
210 /* Get GID of group 'tracing' */
211 grp_tracing
= getgrnam(grp_name
);
213 /* If grp_tracing is NULL, the group does not exist. */
217 /* Get number of supplementary group IDs */
218 grp_list_size
= getgroups(0, NULL
);
219 if (grp_list_size
< 0) {
224 /* Alloc group list of the right size */
225 grp_list
= malloc(grp_list_size
* sizeof(gid_t
));
230 grp_id
= getgroups(grp_list_size
, grp_list
);
236 for (i
= 0; i
< grp_list_size
; i
++) {
237 if (grp_list
[i
] == grp_tracing
->gr_gid
) {
251 * Try connect to session daemon with sock_path.
253 * Return 0 on success, else -1
255 static int try_connect_sessiond(const char *sock_path
)
259 /* If socket exist, we check if the daemon listens for connect. */
260 ret
= access(sock_path
, F_OK
);
266 ret
= lttcomm_connect_unix_sock(sock_path
);
272 ret
= lttcomm_close_unix_sock(ret
);
274 perror("lttcomm_close_unix_sock");
284 * Set sessiond socket path by putting it in the global sessiond_sock_path
287 * Returns 0 on success, negative value on failure (the sessiond socket path
288 * is somehow too long or ENOMEM).
290 static int set_session_daemon_path(void)
292 int in_tgroup
= 0; /* In tracing group */
298 /* Are we in the tracing group ? */
299 in_tgroup
= lttng_check_tracing_group();
302 if ((uid
== 0) || in_tgroup
) {
303 lttng_ctl_copy_string(sessiond_sock_path
,
304 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK
, sizeof(sessiond_sock_path
));
312 ret
= try_connect_sessiond(sessiond_sock_path
);
316 /* Global session daemon not available... */
318 /* ...or not in tracing group (and not root), default */
321 * With GNU C < 2.1, snprintf returns -1 if the target buffer is too small;
322 * With GNU C >= 2.1, snprintf returns the required size (excluding closing null)
324 ret
= snprintf(sessiond_sock_path
, sizeof(sessiond_sock_path
),
325 DEFAULT_HOME_CLIENT_UNIX_SOCK
, utils_get_home_dir());
326 if ((ret
< 0) || (ret
>= sizeof(sessiond_sock_path
))) {
338 * Connect to the LTTng session daemon.
340 * On success, return 0. On error, return -1.
342 static int connect_sessiond(void)
346 /* Don't try to connect if already connected. */
351 ret
= set_session_daemon_path();
356 /* Connect to the sesssion daemon */
357 ret
= lttcomm_connect_unix_sock(sessiond_sock_path
);
362 sessiond_socket
= ret
;
372 * Clean disconnect from the session daemon.
373 * On success, return 0. On error, return -1.
375 static int disconnect_sessiond(void)
380 ret
= lttcomm_close_unix_sock(sessiond_socket
);
389 * Ask the session daemon a specific command and put the data into buf.
390 * Takes extra var. len. data as input to send to the session daemon.
392 * Return size of data (only payload, not header) or a negative error code.
395 int lttng_ctl_ask_sessiond_varlen(struct lttcomm_session_msg
*lsm
,
396 void *vardata
, size_t varlen
, void **buf
)
401 struct lttcomm_lttng_msg llm
;
403 ret
= connect_sessiond();
405 ret
= -LTTNG_ERR_NO_SESSIOND
;
409 /* Send command to session daemon */
410 ret
= send_session_msg(lsm
);
412 /* Ret value is a valid lttng error code. */
415 /* Send var len data */
416 ret
= send_session_varlen(vardata
, varlen
);
418 /* Ret value is a valid lttng error code. */
422 /* Get header from data transmission */
423 ret
= recv_data_sessiond(&llm
, sizeof(llm
));
425 /* Ret value is a valid lttng error code. */
429 /* Check error code if OK */
430 if (llm
.ret_code
!= LTTNG_OK
) {
435 size
= llm
.data_size
;
437 /* If client free with size 0 */
445 data
= (void*) malloc(size
);
447 /* Get payload data */
448 ret
= recv_data_sessiond(data
, size
);
455 * Extra protection not to dereference a NULL pointer. If buf is NULL at
456 * this point, an error is returned and data is freed.
459 ret
= -LTTNG_ERR_INVALID
;
468 disconnect_sessiond();
473 * Create lttng handle and return pointer.
474 * The returned pointer will be NULL in case of malloc() error.
476 struct lttng_handle
*lttng_create_handle(const char *session_name
,
477 struct lttng_domain
*domain
)
479 struct lttng_handle
*handle
= NULL
;
481 if (domain
== NULL
) {
485 handle
= malloc(sizeof(struct lttng_handle
));
486 if (handle
== NULL
) {
487 PERROR("malloc handle");
491 /* Copy session name */
492 lttng_ctl_copy_string(handle
->session_name
, session_name
,
493 sizeof(handle
->session_name
));
495 /* Copy lttng domain */
496 lttng_ctl_copy_lttng_domain(&handle
->domain
, domain
);
503 * Destroy handle by free(3) the pointer.
505 void lttng_destroy_handle(struct lttng_handle
*handle
)
511 * Register an outside consumer.
512 * Returns size of returned session payload data or a negative error code.
514 int lttng_register_consumer(struct lttng_handle
*handle
,
515 const char *socket_path
)
517 struct lttcomm_session_msg lsm
;
519 if (handle
== NULL
|| socket_path
== NULL
) {
520 return -LTTNG_ERR_INVALID
;
523 memset(&lsm
, 0, sizeof(lsm
));
524 lsm
.cmd_type
= LTTNG_REGISTER_CONSUMER
;
525 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
526 sizeof(lsm
.session
.name
));
527 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
529 lttng_ctl_copy_string(lsm
.u
.reg
.path
, socket_path
, sizeof(lsm
.u
.reg
.path
));
531 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
535 * Start tracing for all traces of the session.
536 * Returns size of returned session payload data or a negative error code.
538 int lttng_start_tracing(const char *session_name
)
540 struct lttcomm_session_msg lsm
;
542 if (session_name
== NULL
) {
543 return -LTTNG_ERR_INVALID
;
546 memset(&lsm
, 0, sizeof(lsm
));
547 lsm
.cmd_type
= LTTNG_START_TRACE
;
549 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
550 sizeof(lsm
.session
.name
));
552 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
556 * Stop tracing for all traces of the session.
558 static int _lttng_stop_tracing(const char *session_name
, int wait
)
561 struct lttcomm_session_msg lsm
;
563 if (session_name
== NULL
) {
564 return -LTTNG_ERR_INVALID
;
567 memset(&lsm
, 0, sizeof(lsm
));
568 lsm
.cmd_type
= LTTNG_STOP_TRACE
;
570 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
571 sizeof(lsm
.session
.name
));
573 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
574 if (ret
< 0 && ret
!= -LTTNG_ERR_TRACE_ALREADY_STOPPED
) {
582 /* Check for data availability */
584 data_ret
= lttng_data_pending(session_name
);
586 /* Return the data available call error. */
592 * Data sleep time before retrying (in usec). Don't sleep if the call
593 * returned value indicates availability.
596 usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME
);
598 } while (data_ret
!= 0);
606 * Stop tracing and wait for data availability.
608 int lttng_stop_tracing(const char *session_name
)
610 return _lttng_stop_tracing(session_name
, 1);
614 * Stop tracing but _don't_ wait for data availability.
616 int lttng_stop_tracing_no_wait(const char *session_name
)
618 return _lttng_stop_tracing(session_name
, 0);
622 * Add context to a channel.
624 * If the given channel is NULL, add the contexts to all channels.
625 * The event_name param is ignored.
627 * Returns the size of the returned payload data or a negative error code.
629 int lttng_add_context(struct lttng_handle
*handle
,
630 struct lttng_event_context
*ctx
, const char *event_name
,
631 const char *channel_name
)
633 struct lttcomm_session_msg lsm
;
635 /* Safety check. Both are mandatory */
636 if (handle
== NULL
|| ctx
== NULL
) {
637 return -LTTNG_ERR_INVALID
;
640 memset(&lsm
, 0, sizeof(lsm
));
642 lsm
.cmd_type
= LTTNG_ADD_CONTEXT
;
644 /* If no channel name, send empty string. */
645 if (channel_name
== NULL
) {
646 lttng_ctl_copy_string(lsm
.u
.context
.channel_name
, "",
647 sizeof(lsm
.u
.context
.channel_name
));
649 lttng_ctl_copy_string(lsm
.u
.context
.channel_name
, channel_name
,
650 sizeof(lsm
.u
.context
.channel_name
));
653 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
655 memcpy(&lsm
.u
.context
.ctx
, ctx
, sizeof(struct lttng_event_context
));
657 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
658 sizeof(lsm
.session
.name
));
660 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
664 * Enable event(s) for a channel.
665 * If no event name is specified, all events are enabled.
666 * If no channel name is specified, the default 'channel0' is used.
667 * Returns size of returned session payload data or a negative error code.
669 int lttng_enable_event(struct lttng_handle
*handle
,
670 struct lttng_event
*ev
, const char *channel_name
)
672 return lttng_enable_event_with_exclusions(handle
, ev
, channel_name
,
677 * Create or enable an event with a filter expression.
679 * Return negative error value on error.
680 * Return size of returned session payload data if OK.
682 int lttng_enable_event_with_filter(struct lttng_handle
*handle
,
683 struct lttng_event
*event
, const char *channel_name
,
684 const char *filter_expression
)
686 return lttng_enable_event_with_exclusions(handle
, event
, channel_name
,
687 filter_expression
, 0, NULL
);
691 * Depending on the event, return a newly allocated JUL filter expression or
692 * NULL if not applicable.
694 * An event with NO loglevel and the name is * will return NULL.
696 static char *set_jul_filter(const char *filter
, struct lttng_event
*ev
)
699 char *jul_filter
= NULL
;
703 /* Don't add filter for the '*' event. */
704 if (ev
->name
[0] != '*') {
706 err
= asprintf(&jul_filter
, "%s && logger_name == \"%s\"", filter
,
709 err
= asprintf(&jul_filter
, "logger_name == \"%s\"", ev
->name
);
717 /* Add loglevel filtering if any for the JUL domain. */
718 if (ev
->loglevel_type
!= LTTNG_EVENT_LOGLEVEL_ALL
) {
721 if (ev
->loglevel_type
== LTTNG_EVENT_LOGLEVEL_RANGE
) {
728 err
= asprintf(&jul_filter
, "%s && int_loglevel %s %d", filter
, op
,
731 err
= asprintf(&jul_filter
, "int_loglevel %s %d", op
,
747 * Generate the filter bytecode from a give filter expression string. Put the
748 * newly allocated parser context in ctxp and populate the lsm object with the
751 * Return 0 on success else a LTTNG_ERR_* code and ctxp is untouched.
753 static int generate_filter(char *filter_expression
,
754 struct lttcomm_session_msg
*lsm
, struct filter_parser_ctx
**ctxp
)
757 struct filter_parser_ctx
*ctx
= NULL
;
760 assert(filter_expression
);
765 * Casting const to non-const, as the underlying function will use it in
768 fmem
= lttng_fmemopen((void *) filter_expression
,
769 strlen(filter_expression
), "r");
771 fprintf(stderr
, "Error opening memory as stream\n");
772 ret
= -LTTNG_ERR_FILTER_NOMEM
;
775 ctx
= filter_parser_ctx_alloc(fmem
);
777 fprintf(stderr
, "Error allocating parser\n");
778 ret
= -LTTNG_ERR_FILTER_NOMEM
;
779 goto filter_alloc_error
;
781 ret
= filter_parser_ctx_append_ast(ctx
);
783 fprintf(stderr
, "Parse error\n");
784 ret
= -LTTNG_ERR_FILTER_INVAL
;
787 ret
= filter_visitor_set_parent(ctx
);
789 fprintf(stderr
, "Set parent error\n");
790 ret
= -LTTNG_ERR_FILTER_INVAL
;
794 ret
= filter_visitor_print_xml(ctx
, stdout
, 0);
797 fprintf(stderr
, "XML print error\n");
798 ret
= -LTTNG_ERR_FILTER_INVAL
;
803 dbg_printf("Generating IR... ");
805 ret
= filter_visitor_ir_generate(ctx
);
807 fprintf(stderr
, "Generate IR error\n");
808 ret
= -LTTNG_ERR_FILTER_INVAL
;
811 dbg_printf("done\n");
813 dbg_printf("Validating IR... ");
815 ret
= filter_visitor_ir_check_binary_op_nesting(ctx
);
817 ret
= -LTTNG_ERR_FILTER_INVAL
;
820 dbg_printf("done\n");
822 dbg_printf("Generating bytecode... ");
824 ret
= filter_visitor_bytecode_generate(ctx
);
826 fprintf(stderr
, "Generate bytecode error\n");
827 ret
= -LTTNG_ERR_FILTER_INVAL
;
830 dbg_printf("done\n");
831 dbg_printf("Size of bytecode generated: %u bytes.\n",
832 bytecode_get_len(&ctx
->bytecode
->b
));
834 lsm
->u
.enable
.bytecode_len
= sizeof(ctx
->bytecode
->b
)
835 + bytecode_get_len(&ctx
->bytecode
->b
);
836 lsm
->u
.enable
.expression_len
= strlen(filter_expression
) + 1;
838 /* No need to keep the memory stream. */
839 if (fclose(fmem
) != 0) {
847 filter_bytecode_free(ctx
);
849 filter_parser_ctx_free(ctx
);
851 if (fclose(fmem
) != 0) {
859 * Enable event(s) for a channel, possibly with exclusions and a filter.
860 * If no event name is specified, all events are enabled.
861 * If no channel name is specified, the default name is used.
862 * If filter expression is not NULL, the filter is set for the event.
863 * If exclusion count is not zero, the exclusions are set for the event.
864 * Returns size of returned session payload data or a negative error code.
866 int lttng_enable_event_with_exclusions(struct lttng_handle
*handle
,
867 struct lttng_event
*ev
, const char *channel_name
,
868 const char *original_filter_expression
,
869 int exclusion_count
, char **exclusion_list
)
871 struct lttcomm_session_msg lsm
;
874 unsigned int free_filter_expression
= 0;
875 struct filter_parser_ctx
*ctx
= NULL
;
877 * Cast as non-const since we may replace the filter expression
878 * by a dynamically allocated string. Otherwise, the original
879 * string is not modified.
881 char *filter_expression
= (char *) original_filter_expression
;
883 if (handle
== NULL
|| ev
== NULL
) {
884 ret
= -LTTNG_ERR_INVALID
;
888 /* Empty filter string will always be rejected by the parser
889 * anyway, so treat this corner-case early to eliminate
890 * lttng_fmemopen error for 0-byte allocation.
892 if (filter_expression
&& filter_expression
[0] == '\0') {
893 ret
= -LTTNG_ERR_INVALID
;
897 memset(&lsm
, 0, sizeof(lsm
));
899 /* If no channel name, send empty string. */
900 if (channel_name
== NULL
) {
901 lttng_ctl_copy_string(lsm
.u
.enable
.channel_name
, "",
902 sizeof(lsm
.u
.enable
.channel_name
));
904 lttng_ctl_copy_string(lsm
.u
.enable
.channel_name
, channel_name
,
905 sizeof(lsm
.u
.enable
.channel_name
));
908 if (ev
->name
[0] != '\0') {
909 lsm
.cmd_type
= LTTNG_ENABLE_EVENT
;
911 lsm
.cmd_type
= LTTNG_ENABLE_ALL_EVENT
;
914 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
915 memcpy(&lsm
.u
.enable
.event
, ev
, sizeof(lsm
.u
.enable
.event
));
917 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
918 sizeof(lsm
.session
.name
));
919 lsm
.u
.enable
.exclusion_count
= exclusion_count
;
920 lsm
.u
.enable
.bytecode_len
= 0;
923 * For the JUL domain, a filter is enforced except for the enable all
924 * event. This is done to avoid having the event in all sessions thus
925 * filtering by logger name.
927 if (exclusion_count
== 0 && filter_expression
== NULL
&&
928 handle
->domain
.type
!= LTTNG_DOMAIN_JUL
) {
933 * We have either a filter or some exclusions, so we need to set up
934 * a variable-length memory block from where to send the data
937 /* Parse filter expression */
938 if (filter_expression
!= NULL
|| handle
->domain
.type
== LTTNG_DOMAIN_JUL
) {
939 if (handle
->domain
.type
== LTTNG_DOMAIN_JUL
) {
942 /* Setup JUL filter if needed. */
943 jul_filter
= set_jul_filter(filter_expression
, ev
);
945 if (!filter_expression
) {
946 /* No JUL and no filter, just skip everything below. */
951 * With a JUL filter, the original filter has been added to it
952 * thus replace the filter expression.
954 filter_expression
= jul_filter
;
955 free_filter_expression
= 1;
959 ret
= generate_filter(filter_expression
, &lsm
, &ctx
);
965 varlen_data
= zmalloc(lsm
.u
.enable
.bytecode_len
966 + lsm
.u
.enable
.expression_len
967 + LTTNG_SYMBOL_NAME_LEN
* exclusion_count
);
969 ret
= -LTTNG_ERR_EXCLUSION_NOMEM
;
973 /* Put exclusion names first in the data */
974 while (exclusion_count
--) {
975 strncpy(varlen_data
+ LTTNG_SYMBOL_NAME_LEN
* exclusion_count
,
976 *(exclusion_list
+ exclusion_count
), LTTNG_SYMBOL_NAME_LEN
);
978 /* Add filter expression next */
979 if (lsm
.u
.enable
.expression_len
!= 0) {
981 + LTTNG_SYMBOL_NAME_LEN
* lsm
.u
.enable
.exclusion_count
,
983 lsm
.u
.enable
.expression_len
);
985 /* Add filter bytecode next */
986 if (ctx
&& lsm
.u
.enable
.bytecode_len
!= 0) {
988 + LTTNG_SYMBOL_NAME_LEN
* lsm
.u
.enable
.exclusion_count
989 + lsm
.u
.enable
.expression_len
,
991 lsm
.u
.enable
.bytecode_len
);
994 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, varlen_data
,
995 (LTTNG_SYMBOL_NAME_LEN
* lsm
.u
.enable
.exclusion_count
) +
996 lsm
.u
.enable
.bytecode_len
+ lsm
.u
.enable
.expression_len
, NULL
);
1000 if (filter_expression
) {
1001 filter_bytecode_free(ctx
);
1002 filter_ir_free(ctx
);
1003 filter_parser_ctx_free(ctx
);
1004 if (free_filter_expression
) {
1006 * The filter expression has been replaced and must be
1007 * freed as it is not the original filter expression
1008 * received as a parameter.
1010 free(filter_expression
);
1015 * Return directly to the caller and don't ask the sessiond since something
1016 * went wrong in the parsing of data above.
1021 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
1026 * Disable event(s) of a channel and domain.
1027 * If no event name is specified, all events are disabled.
1028 * If no channel name is specified, the default 'channel0' is used.
1029 * Returns size of returned session payload data or a negative error code.
1031 int lttng_disable_event(struct lttng_handle
*handle
, const char *name
,
1032 const char *channel_name
)
1034 struct lttcomm_session_msg lsm
;
1036 if (handle
== NULL
) {
1037 return -LTTNG_ERR_INVALID
;
1040 memset(&lsm
, 0, sizeof(lsm
));
1042 /* If no channel name, send empty string. */
1043 if (channel_name
== NULL
) {
1044 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, "",
1045 sizeof(lsm
.u
.disable
.channel_name
));
1047 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, channel_name
,
1048 sizeof(lsm
.u
.disable
.channel_name
));
1051 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1054 lttng_ctl_copy_string(lsm
.u
.disable
.name
, name
,
1055 sizeof(lsm
.u
.disable
.name
));
1056 lsm
.cmd_type
= LTTNG_DISABLE_EVENT
;
1058 lsm
.cmd_type
= LTTNG_DISABLE_ALL_EVENT
;
1061 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1062 sizeof(lsm
.session
.name
));
1064 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1068 * Enable channel per domain
1069 * Returns size of returned session payload data or a negative error code.
1071 int lttng_enable_channel(struct lttng_handle
*handle
,
1072 struct lttng_channel
*chan
)
1074 struct lttcomm_session_msg lsm
;
1077 * NULL arguments are forbidden. No default values.
1079 if (handle
== NULL
|| chan
== NULL
) {
1080 return -LTTNG_ERR_INVALID
;
1083 memset(&lsm
, 0, sizeof(lsm
));
1085 memcpy(&lsm
.u
.channel
.chan
, chan
, sizeof(lsm
.u
.channel
.chan
));
1087 lsm
.cmd_type
= LTTNG_ENABLE_CHANNEL
;
1089 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1091 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1092 sizeof(lsm
.session
.name
));
1094 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1098 * All tracing will be stopped for registered events of the channel.
1099 * Returns size of returned session payload data or a negative error code.
1101 int lttng_disable_channel(struct lttng_handle
*handle
, const char *name
)
1103 struct lttcomm_session_msg lsm
;
1105 /* Safety check. Both are mandatory */
1106 if (handle
== NULL
|| name
== NULL
) {
1107 return -LTTNG_ERR_INVALID
;
1110 memset(&lsm
, 0, sizeof(lsm
));
1112 lsm
.cmd_type
= LTTNG_DISABLE_CHANNEL
;
1114 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, name
,
1115 sizeof(lsm
.u
.disable
.channel_name
));
1117 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1119 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1120 sizeof(lsm
.session
.name
));
1122 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1126 * Lists all available tracepoints of domain.
1127 * Sets the contents of the events array.
1128 * Returns the number of lttng_event entries in events;
1129 * on error, returns a negative value.
1131 int lttng_list_tracepoints(struct lttng_handle
*handle
,
1132 struct lttng_event
**events
)
1135 struct lttcomm_session_msg lsm
;
1137 if (handle
== NULL
) {
1138 return -LTTNG_ERR_INVALID
;
1141 memset(&lsm
, 0, sizeof(lsm
));
1142 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINTS
;
1143 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1145 ret
= lttng_ctl_ask_sessiond(&lsm
, (void **) events
);
1150 return ret
/ sizeof(struct lttng_event
);
1154 * Lists all available tracepoint fields of domain.
1155 * Sets the contents of the event field array.
1156 * Returns the number of lttng_event_field entries in events;
1157 * on error, returns a negative value.
1159 int lttng_list_tracepoint_fields(struct lttng_handle
*handle
,
1160 struct lttng_event_field
**fields
)
1163 struct lttcomm_session_msg lsm
;
1165 if (handle
== NULL
) {
1166 return -LTTNG_ERR_INVALID
;
1169 memset(&lsm
, 0, sizeof(lsm
));
1170 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINT_FIELDS
;
1171 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1173 ret
= lttng_ctl_ask_sessiond(&lsm
, (void **) fields
);
1178 return ret
/ sizeof(struct lttng_event_field
);
1182 * Returns a human readable string describing
1183 * the error code (a negative value).
1185 const char *lttng_strerror(int code
)
1187 return error_get_str(code
);
1191 * Create a brand new session using name and url for destination.
1193 * Returns LTTNG_OK on success or a negative error code.
1195 int lttng_create_session(const char *name
, const char *url
)
1199 struct lttcomm_session_msg lsm
;
1200 struct lttng_uri
*uris
= NULL
;
1203 return -LTTNG_ERR_INVALID
;
1206 memset(&lsm
, 0, sizeof(lsm
));
1208 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1209 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1211 /* There should never be a data URL */
1212 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1214 return -LTTNG_ERR_INVALID
;
1217 lsm
.u
.uri
.size
= size
;
1219 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1220 sizeof(struct lttng_uri
) * size
, NULL
);
1227 * Destroy session using name.
1228 * Returns size of returned session payload data or a negative error code.
1230 int lttng_destroy_session(const char *session_name
)
1232 struct lttcomm_session_msg lsm
;
1234 if (session_name
== NULL
) {
1235 return -LTTNG_ERR_INVALID
;
1238 memset(&lsm
, 0, sizeof(lsm
));
1239 lsm
.cmd_type
= LTTNG_DESTROY_SESSION
;
1241 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1242 sizeof(lsm
.session
.name
));
1244 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1248 * Ask the session daemon for all available sessions.
1249 * Sets the contents of the sessions array.
1250 * Returns the number of lttng_session entries in sessions;
1251 * on error, returns a negative value.
1253 int lttng_list_sessions(struct lttng_session
**sessions
)
1256 struct lttcomm_session_msg lsm
;
1258 memset(&lsm
, 0, sizeof(lsm
));
1259 lsm
.cmd_type
= LTTNG_LIST_SESSIONS
;
1260 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) sessions
);
1265 return ret
/ sizeof(struct lttng_session
);
1269 * Ask the session daemon for all available domains of a session.
1270 * Sets the contents of the domains array.
1271 * Returns the number of lttng_domain entries in domains;
1272 * on error, returns a negative value.
1274 int lttng_list_domains(const char *session_name
,
1275 struct lttng_domain
**domains
)
1278 struct lttcomm_session_msg lsm
;
1280 if (session_name
== NULL
) {
1281 return -LTTNG_ERR_INVALID
;
1284 memset(&lsm
, 0, sizeof(lsm
));
1285 lsm
.cmd_type
= LTTNG_LIST_DOMAINS
;
1287 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1288 sizeof(lsm
.session
.name
));
1290 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) domains
);
1295 return ret
/ sizeof(struct lttng_domain
);
1299 * Ask the session daemon for all available channels of a session.
1300 * Sets the contents of the channels array.
1301 * Returns the number of lttng_channel entries in channels;
1302 * on error, returns a negative value.
1304 int lttng_list_channels(struct lttng_handle
*handle
,
1305 struct lttng_channel
**channels
)
1308 struct lttcomm_session_msg lsm
;
1310 if (handle
== NULL
) {
1311 return -LTTNG_ERR_INVALID
;
1314 memset(&lsm
, 0, sizeof(lsm
));
1315 lsm
.cmd_type
= LTTNG_LIST_CHANNELS
;
1316 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1317 sizeof(lsm
.session
.name
));
1319 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1321 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) channels
);
1326 return ret
/ sizeof(struct lttng_channel
);
1330 * Ask the session daemon for all available events of a session channel.
1331 * Sets the contents of the events array.
1332 * Returns the number of lttng_event entries in events;
1333 * on error, returns a negative value.
1335 int lttng_list_events(struct lttng_handle
*handle
,
1336 const char *channel_name
, struct lttng_event
**events
)
1339 struct lttcomm_session_msg lsm
;
1341 /* Safety check. An handle and channel name are mandatory */
1342 if (handle
== NULL
|| channel_name
== NULL
) {
1343 return -LTTNG_ERR_INVALID
;
1346 memset(&lsm
, 0, sizeof(lsm
));
1347 lsm
.cmd_type
= LTTNG_LIST_EVENTS
;
1348 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1349 sizeof(lsm
.session
.name
));
1350 lttng_ctl_copy_string(lsm
.u
.list
.channel_name
, channel_name
,
1351 sizeof(lsm
.u
.list
.channel_name
));
1353 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1355 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) events
);
1360 return ret
/ sizeof(struct lttng_event
);
1364 * Sets the tracing_group variable with name.
1365 * This function allocates memory pointed to by tracing_group.
1366 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
1368 int lttng_set_tracing_group(const char *name
)
1371 return -LTTNG_ERR_INVALID
;
1374 if (asprintf(&tracing_group
, "%s", name
) < 0) {
1375 return -LTTNG_ERR_FATAL
;
1382 * Returns size of returned session payload data or a negative error code.
1384 int lttng_calibrate(struct lttng_handle
*handle
,
1385 struct lttng_calibrate
*calibrate
)
1387 struct lttcomm_session_msg lsm
;
1389 /* Safety check. NULL pointer are forbidden */
1390 if (handle
== NULL
|| calibrate
== NULL
) {
1391 return -LTTNG_ERR_INVALID
;
1394 memset(&lsm
, 0, sizeof(lsm
));
1395 lsm
.cmd_type
= LTTNG_CALIBRATE
;
1396 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1398 memcpy(&lsm
.u
.calibrate
, calibrate
, sizeof(lsm
.u
.calibrate
));
1400 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1404 * Set default channel attributes.
1405 * If either or both of the arguments are null, attr content is zeroe'd.
1407 void lttng_channel_set_default_attr(struct lttng_domain
*domain
,
1408 struct lttng_channel_attr
*attr
)
1411 if (attr
== NULL
|| domain
== NULL
) {
1415 memset(attr
, 0, sizeof(struct lttng_channel_attr
));
1417 /* Same for all domains. */
1418 attr
->overwrite
= DEFAULT_CHANNEL_OVERWRITE
;
1419 attr
->tracefile_size
= DEFAULT_CHANNEL_TRACEFILE_SIZE
;
1420 attr
->tracefile_count
= DEFAULT_CHANNEL_TRACEFILE_COUNT
;
1422 switch (domain
->type
) {
1423 case LTTNG_DOMAIN_KERNEL
:
1424 attr
->switch_timer_interval
= DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER
;
1425 attr
->read_timer_interval
= DEFAULT_KERNEL_CHANNEL_READ_TIMER
;
1426 attr
->subbuf_size
= default_get_kernel_channel_subbuf_size();
1427 attr
->num_subbuf
= DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM
;
1428 attr
->output
= DEFAULT_KERNEL_CHANNEL_OUTPUT
;
1430 case LTTNG_DOMAIN_UST
:
1431 switch (domain
->buf_type
) {
1432 case LTTNG_BUFFER_PER_UID
:
1433 attr
->subbuf_size
= default_get_ust_uid_channel_subbuf_size();
1434 attr
->num_subbuf
= DEFAULT_UST_UID_CHANNEL_SUBBUF_NUM
;
1435 attr
->output
= DEFAULT_UST_UID_CHANNEL_OUTPUT
;
1436 attr
->switch_timer_interval
= DEFAULT_UST_UID_CHANNEL_SWITCH_TIMER
;
1437 attr
->read_timer_interval
= DEFAULT_UST_UID_CHANNEL_READ_TIMER
;
1439 case LTTNG_BUFFER_PER_PID
:
1441 attr
->subbuf_size
= default_get_ust_pid_channel_subbuf_size();
1442 attr
->num_subbuf
= DEFAULT_UST_PID_CHANNEL_SUBBUF_NUM
;
1443 attr
->output
= DEFAULT_UST_PID_CHANNEL_OUTPUT
;
1444 attr
->switch_timer_interval
= DEFAULT_UST_PID_CHANNEL_SWITCH_TIMER
;
1445 attr
->read_timer_interval
= DEFAULT_UST_PID_CHANNEL_READ_TIMER
;
1449 /* Default behavior: leave set to 0. */
1455 * Check if session daemon is alive.
1457 * Return 1 if alive or 0 if not.
1458 * On error returns a negative value.
1460 int lttng_session_daemon_alive(void)
1464 ret
= set_session_daemon_path();
1470 if (*sessiond_sock_path
== '\0') {
1472 * No socket path set. Weird error which means the constructor was not
1478 ret
= try_connect_sessiond(sessiond_sock_path
);
1489 * Set URL for a consumer for a session and domain.
1491 * Return 0 on success, else a negative value.
1493 int lttng_set_consumer_url(struct lttng_handle
*handle
,
1494 const char *control_url
, const char *data_url
)
1498 struct lttcomm_session_msg lsm
;
1499 struct lttng_uri
*uris
= NULL
;
1501 if (handle
== NULL
|| (control_url
== NULL
&& data_url
== NULL
)) {
1502 return -LTTNG_ERR_INVALID
;
1505 memset(&lsm
, 0, sizeof(lsm
));
1507 lsm
.cmd_type
= LTTNG_SET_CONSUMER_URI
;
1509 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1510 sizeof(lsm
.session
.name
));
1511 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1513 size
= uri_parse_str_urls(control_url
, data_url
, &uris
);
1515 return -LTTNG_ERR_INVALID
;
1518 lsm
.u
.uri
.size
= size
;
1520 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1521 sizeof(struct lttng_uri
) * size
, NULL
);
1530 int lttng_enable_consumer(struct lttng_handle
*handle
)
1538 int lttng_disable_consumer(struct lttng_handle
*handle
)
1544 * This is an extension of create session that is ONLY and SHOULD only be used
1545 * by the lttng command line program. It exists to avoid using URI parsing in
1548 * We need the date and time for the trace path subdirectory for the case where
1549 * the user does NOT define one using either -o or -U. Using the normal
1550 * lttng_create_session API call, we have no clue on the session daemon side if
1551 * the URL was generated automatically by the client or define by the user.
1553 * So this function "wrapper" is hidden from the public API, takes the datetime
1554 * string and appends it if necessary to the URI subdirectory before sending it
1555 * to the session daemon.
1557 * With this extra function, the lttng_create_session call behavior is not
1558 * changed and the timestamp is appended to the URI on the session daemon side
1561 int _lttng_create_session_ext(const char *name
, const char *url
,
1562 const char *datetime
)
1566 struct lttcomm_session_msg lsm
;
1567 struct lttng_uri
*uris
= NULL
;
1569 if (name
== NULL
|| datetime
== NULL
) {
1570 return -LTTNG_ERR_INVALID
;
1573 memset(&lsm
, 0, sizeof(lsm
));
1575 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1576 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1578 /* There should never be a data URL */
1579 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1581 ret
= -LTTNG_ERR_INVALID
;
1585 lsm
.u
.uri
.size
= size
;
1587 if (size
> 0 && uris
[0].dtype
!= LTTNG_DST_PATH
&& strlen(uris
[0].subdir
) == 0) {
1588 /* Don't append datetime if the name was automatically created. */
1589 if (strncmp(name
, DEFAULT_SESSION_NAME
"-",
1590 strlen(DEFAULT_SESSION_NAME
) + 1)) {
1591 ret
= snprintf(uris
[0].subdir
, sizeof(uris
[0].subdir
), "%s-%s",
1594 ret
= snprintf(uris
[0].subdir
, sizeof(uris
[0].subdir
), "%s", name
);
1597 PERROR("snprintf uri subdir");
1598 ret
= -LTTNG_ERR_FATAL
;
1603 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1604 sizeof(struct lttng_uri
) * size
, NULL
);
1612 * For a given session name, this call checks if the data is ready to be read
1613 * or is still being extracted by the consumer(s) hence not ready to be used by
1616 int lttng_data_pending(const char *session_name
)
1619 struct lttcomm_session_msg lsm
;
1621 if (session_name
== NULL
) {
1622 return -LTTNG_ERR_INVALID
;
1625 memset(&lsm
, 0, sizeof(lsm
));
1626 lsm
.cmd_type
= LTTNG_DATA_PENDING
;
1628 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1629 sizeof(lsm
.session
.name
));
1631 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
1634 * The lttng_ctl_ask_sessiond function negate the return code if it's not
1635 * LTTNG_OK so getting -1 means that the reply ret_code was 1 thus meaning
1636 * that the data is available. Yes it is hackish but for now this is the
1647 * Create a session exclusively used for snapshot.
1649 * Returns LTTNG_OK on success or a negative error code.
1651 int lttng_create_session_snapshot(const char *name
, const char *snapshot_url
)
1655 struct lttcomm_session_msg lsm
;
1656 struct lttng_uri
*uris
= NULL
;
1659 return -LTTNG_ERR_INVALID
;
1662 memset(&lsm
, 0, sizeof(lsm
));
1664 lsm
.cmd_type
= LTTNG_CREATE_SESSION_SNAPSHOT
;
1665 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1667 size
= uri_parse_str_urls(snapshot_url
, NULL
, &uris
);
1669 return -LTTNG_ERR_INVALID
;
1672 lsm
.u
.uri
.size
= size
;
1674 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1675 sizeof(struct lttng_uri
) * size
, NULL
);
1682 * Create a session exclusively used for live.
1684 * Returns LTTNG_OK on success or a negative error code.
1686 int lttng_create_session_live(const char *name
, const char *url
,
1687 unsigned int timer_interval
)
1691 struct lttcomm_session_msg lsm
;
1692 struct lttng_uri
*uris
= NULL
;
1695 return -LTTNG_ERR_INVALID
;
1698 memset(&lsm
, 0, sizeof(lsm
));
1700 lsm
.cmd_type
= LTTNG_CREATE_SESSION_LIVE
;
1701 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1704 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1706 ret
= -LTTNG_ERR_INVALID
;
1710 /* file:// is not accepted for live session. */
1711 if (uris
[0].dtype
== LTTNG_DST_PATH
) {
1712 ret
= -LTTNG_ERR_INVALID
;
1719 lsm
.u
.session_live
.nb_uri
= size
;
1720 lsm
.u
.session_live
.timer_interval
= timer_interval
;
1722 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1723 sizeof(struct lttng_uri
) * size
, NULL
);
1733 static void __attribute__((constructor
)) init()
1735 /* Set default session group */
1736 lttng_set_tracing_group(DEFAULT_TRACING_GROUP
);
1742 static void __attribute__((destructor
)) lttng_ctl_exit()
1744 free(tracing_group
);