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 _MSG("Waiting for data availability");
585 /* Check for data availability */
587 data_ret
= lttng_data_pending(session_name
);
589 /* Return the data available call error. */
595 * Data sleep time before retrying (in usec). Don't sleep if the call
596 * returned value indicates availability.
599 usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME
);
603 } while (data_ret
!= 0);
613 * Stop tracing and wait for data availability.
615 int lttng_stop_tracing(const char *session_name
)
617 return _lttng_stop_tracing(session_name
, 1);
621 * Stop tracing but _don't_ wait for data availability.
623 int lttng_stop_tracing_no_wait(const char *session_name
)
625 return _lttng_stop_tracing(session_name
, 0);
629 * Add context to a channel.
631 * If the given channel is NULL, add the contexts to all channels.
632 * The event_name param is ignored.
634 * Returns the size of the returned payload data or a negative error code.
636 int lttng_add_context(struct lttng_handle
*handle
,
637 struct lttng_event_context
*ctx
, const char *event_name
,
638 const char *channel_name
)
640 struct lttcomm_session_msg lsm
;
642 /* Safety check. Both are mandatory */
643 if (handle
== NULL
|| ctx
== NULL
) {
644 return -LTTNG_ERR_INVALID
;
647 memset(&lsm
, 0, sizeof(lsm
));
649 lsm
.cmd_type
= LTTNG_ADD_CONTEXT
;
651 /* If no channel name, send empty string. */
652 if (channel_name
== NULL
) {
653 lttng_ctl_copy_string(lsm
.u
.context
.channel_name
, "",
654 sizeof(lsm
.u
.context
.channel_name
));
656 lttng_ctl_copy_string(lsm
.u
.context
.channel_name
, channel_name
,
657 sizeof(lsm
.u
.context
.channel_name
));
660 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
662 memcpy(&lsm
.u
.context
.ctx
, ctx
, sizeof(struct lttng_event_context
));
664 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
665 sizeof(lsm
.session
.name
));
667 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
671 * Enable event(s) for a channel.
672 * If no event name is specified, all events are enabled.
673 * If no channel name is specified, the default 'channel0' is used.
674 * Returns size of returned session payload data or a negative error code.
676 int lttng_enable_event(struct lttng_handle
*handle
,
677 struct lttng_event
*ev
, const char *channel_name
)
679 return lttng_enable_event_with_exclusions(handle
, ev
, channel_name
,
684 * Create or enable an event with a filter expression.
686 * Return negative error value on error.
687 * Return size of returned session payload data if OK.
689 int lttng_enable_event_with_filter(struct lttng_handle
*handle
,
690 struct lttng_event
*event
, const char *channel_name
,
691 const char *filter_expression
)
693 return lttng_enable_event_with_exclusions(handle
, event
, channel_name
,
694 filter_expression
, 0, NULL
);
698 * Depending on the event, return a newly allocated JUL filter expression or
699 * NULL if not applicable.
701 * An event with NO loglevel and the name is * will return NULL.
703 static char *set_jul_filter(const char *filter
, struct lttng_event
*ev
)
706 char *jul_filter
= NULL
;
710 /* Don't add filter for the '*' event. */
711 if (ev
->name
[0] != '*') {
713 err
= asprintf(&jul_filter
, "%s && logger_name == \"%s\"", filter
,
716 err
= asprintf(&jul_filter
, "logger_name == \"%s\"", ev
->name
);
724 /* Add loglevel filtering if any for the JUL domain. */
725 if (ev
->loglevel_type
!= LTTNG_EVENT_LOGLEVEL_ALL
) {
728 if (ev
->loglevel_type
== LTTNG_EVENT_LOGLEVEL_RANGE
) {
735 err
= asprintf(&jul_filter
, "%s && int_loglevel %s %d", filter
, op
,
738 err
= asprintf(&jul_filter
, "int_loglevel %s %d", op
,
754 * Enable event(s) for a channel, possibly with exclusions and a filter.
755 * If no event name is specified, all events are enabled.
756 * If no channel name is specified, the default name is used.
757 * If filter expression is not NULL, the filter is set for the event.
758 * If exclusion count is not zero, the exclusions are set for the event.
759 * Returns size of returned session payload data or a negative error code.
761 int lttng_enable_event_with_exclusions(struct lttng_handle
*handle
,
762 struct lttng_event
*ev
, const char *channel_name
,
763 const char *filter_expression
,
764 int exclusion_count
, char **exclusion_list
)
766 struct lttcomm_session_msg lsm
;
769 struct filter_parser_ctx
*ctx
= NULL
;
772 if (handle
== NULL
|| ev
== NULL
) {
773 return -LTTNG_ERR_INVALID
;
776 /* Empty filter string will always be rejected by the parser
777 * anyway, so treat this corner-case early to eliminate
778 * lttng_fmemopen error for 0-byte allocation.
780 if (filter_expression
&& filter_expression
[0] == '\0') {
781 return -LTTNG_ERR_INVALID
;
784 memset(&lsm
, 0, sizeof(lsm
));
786 /* If no channel name, send empty string. */
787 if (channel_name
== NULL
) {
788 lttng_ctl_copy_string(lsm
.u
.enable
.channel_name
, "",
789 sizeof(lsm
.u
.enable
.channel_name
));
791 lttng_ctl_copy_string(lsm
.u
.enable
.channel_name
, channel_name
,
792 sizeof(lsm
.u
.enable
.channel_name
));
795 if (ev
->name
[0] != '\0') {
796 lsm
.cmd_type
= LTTNG_ENABLE_EVENT
;
798 lsm
.cmd_type
= LTTNG_ENABLE_ALL_EVENT
;
801 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
802 memcpy(&lsm
.u
.enable
.event
, ev
, sizeof(lsm
.u
.enable
.event
));
804 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
805 sizeof(lsm
.session
.name
));
806 lsm
.u
.enable
.exclusion_count
= exclusion_count
;
807 lsm
.u
.enable
.bytecode_len
= 0;
810 * For the JUL domain, a filter is enforced except for the enable all
811 * event. This is done to avoid having the event in all sessions thus
812 * filtering by logger name.
814 if (exclusion_count
== 0 && filter_expression
== NULL
&&
815 handle
->domain
.type
!= LTTNG_DOMAIN_JUL
) {
820 * We have either a filter or some exclusions, so we need to set up
821 * a variable-length memory block from where to send the data
824 /* Parse filter expression */
825 if (filter_expression
!= NULL
|| handle
->domain
.type
== LTTNG_DOMAIN_JUL
) {
826 if (handle
->domain
.type
== LTTNG_DOMAIN_JUL
) {
829 /* Setup JUL filter if needed. */
830 jul_filter
= set_jul_filter(filter_expression
, ev
);
832 if (!filter_expression
) {
833 /* No JUL and no filter, just skip everything below. */
838 * With a JUL filter, the original filter has been added to it
839 * thus replace the filter expression.
841 filter_expression
= strdup(jul_filter
);
843 if (!filter_expression
) {
844 return -LTTNG_ERR_FILTER_NOMEM
;
850 * casting const to non-const, as the underlying function will
851 * use it in read-only mode.
853 fmem
= lttng_fmemopen((void *) filter_expression
,
854 strlen(filter_expression
), "r");
856 fprintf(stderr
, "Error opening memory as stream\n");
857 return -LTTNG_ERR_FILTER_NOMEM
;
859 ctx
= filter_parser_ctx_alloc(fmem
);
861 fprintf(stderr
, "Error allocating parser\n");
862 ret
= -LTTNG_ERR_FILTER_NOMEM
;
863 goto filter_alloc_error
;
865 ret
= filter_parser_ctx_append_ast(ctx
);
867 fprintf(stderr
, "Parse error\n");
868 ret
= -LTTNG_ERR_FILTER_INVAL
;
871 ret
= filter_visitor_set_parent(ctx
);
873 fprintf(stderr
, "Set parent error\n");
874 ret
= -LTTNG_ERR_FILTER_INVAL
;
878 ret
= filter_visitor_print_xml(ctx
, stdout
, 0);
881 fprintf(stderr
, "XML print error\n");
882 ret
= -LTTNG_ERR_FILTER_INVAL
;
887 dbg_printf("Generating IR... ");
889 ret
= filter_visitor_ir_generate(ctx
);
891 fprintf(stderr
, "Generate IR error\n");
892 ret
= -LTTNG_ERR_FILTER_INVAL
;
895 dbg_printf("done\n");
897 dbg_printf("Validating IR... ");
899 ret
= filter_visitor_ir_check_binary_op_nesting(ctx
);
901 ret
= -LTTNG_ERR_FILTER_INVAL
;
904 dbg_printf("done\n");
906 dbg_printf("Generating bytecode... ");
908 ret
= filter_visitor_bytecode_generate(ctx
);
910 fprintf(stderr
, "Generate bytecode error\n");
911 ret
= -LTTNG_ERR_FILTER_INVAL
;
914 dbg_printf("done\n");
915 dbg_printf("Size of bytecode generated: %u bytes.\n",
916 bytecode_get_len(&ctx
->bytecode
->b
));
918 lsm
.u
.enable
.bytecode_len
= sizeof(ctx
->bytecode
->b
)
919 + bytecode_get_len(&ctx
->bytecode
->b
);
922 /* Allocate variable length data */
923 if (lsm
.u
.enable
.exclusion_count
!= 0) {
924 varlen_data
= zmalloc(lsm
.u
.enable
.bytecode_len
925 + LTTNG_SYMBOL_NAME_LEN
* exclusion_count
);
927 ret
= -LTTNG_ERR_EXCLUSION_NOMEM
;
928 goto varlen_alloc_error
;
930 /* Put exclusion names first in the data */
931 while (exclusion_count
--) {
932 strncpy(varlen_data
+ LTTNG_SYMBOL_NAME_LEN
* exclusion_count
,
933 *(exclusion_list
+ exclusion_count
),
934 LTTNG_SYMBOL_NAME_LEN
);
936 /* Add filter bytecode next */
937 if (lsm
.u
.enable
.bytecode_len
!= 0) {
938 memcpy(varlen_data
+ LTTNG_SYMBOL_NAME_LEN
* lsm
.u
.enable
.exclusion_count
,
940 lsm
.u
.enable
.bytecode_len
);
943 /* no exclusions - use the already allocated filter bytecode */
944 varlen_data
= (char *)(&ctx
->bytecode
->b
);
947 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, varlen_data
,
948 (LTTNG_SYMBOL_NAME_LEN
* lsm
.u
.enable
.exclusion_count
) +
949 lsm
.u
.enable
.bytecode_len
, NULL
);
951 if (lsm
.u
.enable
.exclusion_count
!= 0) {
956 if (filter_expression
) {
957 filter_bytecode_free(ctx
);
959 filter_parser_ctx_free(ctx
);
960 if (fclose(fmem
) != 0) {
967 filter_bytecode_free(ctx
);
969 filter_parser_ctx_free(ctx
);
971 if (fclose(fmem
) != 0) {
977 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
982 * Disable event(s) of a channel and domain.
983 * If no event name is specified, all events are disabled.
984 * If no channel name is specified, the default 'channel0' is used.
985 * Returns size of returned session payload data or a negative error code.
987 int lttng_disable_event(struct lttng_handle
*handle
, const char *name
,
988 const char *channel_name
)
990 struct lttcomm_session_msg lsm
;
992 if (handle
== NULL
) {
993 return -LTTNG_ERR_INVALID
;
996 memset(&lsm
, 0, sizeof(lsm
));
998 /* If no channel name, send empty string. */
999 if (channel_name
== NULL
) {
1000 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, "",
1001 sizeof(lsm
.u
.disable
.channel_name
));
1003 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, channel_name
,
1004 sizeof(lsm
.u
.disable
.channel_name
));
1007 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1010 lttng_ctl_copy_string(lsm
.u
.disable
.name
, name
,
1011 sizeof(lsm
.u
.disable
.name
));
1012 lsm
.cmd_type
= LTTNG_DISABLE_EVENT
;
1014 lsm
.cmd_type
= LTTNG_DISABLE_ALL_EVENT
;
1017 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1018 sizeof(lsm
.session
.name
));
1020 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1024 * Enable channel per domain
1025 * Returns size of returned session payload data or a negative error code.
1027 int lttng_enable_channel(struct lttng_handle
*handle
,
1028 struct lttng_channel
*chan
)
1030 struct lttcomm_session_msg lsm
;
1033 * NULL arguments are forbidden. No default values.
1035 if (handle
== NULL
|| chan
== NULL
) {
1036 return -LTTNG_ERR_INVALID
;
1039 memset(&lsm
, 0, sizeof(lsm
));
1041 memcpy(&lsm
.u
.channel
.chan
, chan
, sizeof(lsm
.u
.channel
.chan
));
1043 lsm
.cmd_type
= LTTNG_ENABLE_CHANNEL
;
1045 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1047 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1048 sizeof(lsm
.session
.name
));
1050 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1054 * All tracing will be stopped for registered events of the channel.
1055 * Returns size of returned session payload data or a negative error code.
1057 int lttng_disable_channel(struct lttng_handle
*handle
, const char *name
)
1059 struct lttcomm_session_msg lsm
;
1061 /* Safety check. Both are mandatory */
1062 if (handle
== NULL
|| name
== NULL
) {
1063 return -LTTNG_ERR_INVALID
;
1066 memset(&lsm
, 0, sizeof(lsm
));
1068 lsm
.cmd_type
= LTTNG_DISABLE_CHANNEL
;
1070 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, name
,
1071 sizeof(lsm
.u
.disable
.channel_name
));
1073 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1075 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1076 sizeof(lsm
.session
.name
));
1078 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1082 * Lists all available tracepoints of domain.
1083 * Sets the contents of the events array.
1084 * Returns the number of lttng_event entries in events;
1085 * on error, returns a negative value.
1087 int lttng_list_tracepoints(struct lttng_handle
*handle
,
1088 struct lttng_event
**events
)
1091 struct lttcomm_session_msg lsm
;
1093 if (handle
== NULL
) {
1094 return -LTTNG_ERR_INVALID
;
1097 memset(&lsm
, 0, sizeof(lsm
));
1098 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINTS
;
1099 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1101 ret
= lttng_ctl_ask_sessiond(&lsm
, (void **) events
);
1106 return ret
/ sizeof(struct lttng_event
);
1110 * Lists all available tracepoint fields of domain.
1111 * Sets the contents of the event field array.
1112 * Returns the number of lttng_event_field entries in events;
1113 * on error, returns a negative value.
1115 int lttng_list_tracepoint_fields(struct lttng_handle
*handle
,
1116 struct lttng_event_field
**fields
)
1119 struct lttcomm_session_msg lsm
;
1121 if (handle
== NULL
) {
1122 return -LTTNG_ERR_INVALID
;
1125 memset(&lsm
, 0, sizeof(lsm
));
1126 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINT_FIELDS
;
1127 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1129 ret
= lttng_ctl_ask_sessiond(&lsm
, (void **) fields
);
1134 return ret
/ sizeof(struct lttng_event_field
);
1138 * Returns a human readable string describing
1139 * the error code (a negative value).
1141 const char *lttng_strerror(int code
)
1143 return error_get_str(code
);
1147 * Create a brand new session using name and url for destination.
1149 * Returns LTTNG_OK on success or a negative error code.
1151 int lttng_create_session(const char *name
, const char *url
)
1155 struct lttcomm_session_msg lsm
;
1156 struct lttng_uri
*uris
= NULL
;
1159 return -LTTNG_ERR_INVALID
;
1162 memset(&lsm
, 0, sizeof(lsm
));
1164 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1165 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1167 /* There should never be a data URL */
1168 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1170 return -LTTNG_ERR_INVALID
;
1173 lsm
.u
.uri
.size
= size
;
1175 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1176 sizeof(struct lttng_uri
) * size
, NULL
);
1183 * Destroy session using name.
1184 * Returns size of returned session payload data or a negative error code.
1186 int lttng_destroy_session(const char *session_name
)
1188 struct lttcomm_session_msg lsm
;
1190 if (session_name
== NULL
) {
1191 return -LTTNG_ERR_INVALID
;
1194 memset(&lsm
, 0, sizeof(lsm
));
1195 lsm
.cmd_type
= LTTNG_DESTROY_SESSION
;
1197 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1198 sizeof(lsm
.session
.name
));
1200 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1204 * Ask the session daemon for all available sessions.
1205 * Sets the contents of the sessions array.
1206 * Returns the number of lttng_session entries in sessions;
1207 * on error, returns a negative value.
1209 int lttng_list_sessions(struct lttng_session
**sessions
)
1212 struct lttcomm_session_msg lsm
;
1214 memset(&lsm
, 0, sizeof(lsm
));
1215 lsm
.cmd_type
= LTTNG_LIST_SESSIONS
;
1216 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) sessions
);
1221 return ret
/ sizeof(struct lttng_session
);
1225 * Ask the session daemon for all available domains of a session.
1226 * Sets the contents of the domains array.
1227 * Returns the number of lttng_domain entries in domains;
1228 * on error, returns a negative value.
1230 int lttng_list_domains(const char *session_name
,
1231 struct lttng_domain
**domains
)
1234 struct lttcomm_session_msg lsm
;
1236 if (session_name
== NULL
) {
1237 return -LTTNG_ERR_INVALID
;
1240 memset(&lsm
, 0, sizeof(lsm
));
1241 lsm
.cmd_type
= LTTNG_LIST_DOMAINS
;
1243 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1244 sizeof(lsm
.session
.name
));
1246 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) domains
);
1251 return ret
/ sizeof(struct lttng_domain
);
1255 * Ask the session daemon for all available channels of a session.
1256 * Sets the contents of the channels array.
1257 * Returns the number of lttng_channel entries in channels;
1258 * on error, returns a negative value.
1260 int lttng_list_channels(struct lttng_handle
*handle
,
1261 struct lttng_channel
**channels
)
1264 struct lttcomm_session_msg lsm
;
1266 if (handle
== NULL
) {
1267 return -LTTNG_ERR_INVALID
;
1270 memset(&lsm
, 0, sizeof(lsm
));
1271 lsm
.cmd_type
= LTTNG_LIST_CHANNELS
;
1272 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1273 sizeof(lsm
.session
.name
));
1275 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1277 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) channels
);
1282 return ret
/ sizeof(struct lttng_channel
);
1286 * Ask the session daemon for all available events of a session channel.
1287 * Sets the contents of the events array.
1288 * Returns the number of lttng_event entries in events;
1289 * on error, returns a negative value.
1291 int lttng_list_events(struct lttng_handle
*handle
,
1292 const char *channel_name
, struct lttng_event
**events
)
1295 struct lttcomm_session_msg lsm
;
1297 /* Safety check. An handle and channel name are mandatory */
1298 if (handle
== NULL
|| channel_name
== NULL
) {
1299 return -LTTNG_ERR_INVALID
;
1302 memset(&lsm
, 0, sizeof(lsm
));
1303 lsm
.cmd_type
= LTTNG_LIST_EVENTS
;
1304 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1305 sizeof(lsm
.session
.name
));
1306 lttng_ctl_copy_string(lsm
.u
.list
.channel_name
, channel_name
,
1307 sizeof(lsm
.u
.list
.channel_name
));
1309 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1311 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) events
);
1316 return ret
/ sizeof(struct lttng_event
);
1320 * Sets the tracing_group variable with name.
1321 * This function allocates memory pointed to by tracing_group.
1322 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
1324 int lttng_set_tracing_group(const char *name
)
1327 return -LTTNG_ERR_INVALID
;
1330 if (asprintf(&tracing_group
, "%s", name
) < 0) {
1331 return -LTTNG_ERR_FATAL
;
1338 * Returns size of returned session payload data or a negative error code.
1340 int lttng_calibrate(struct lttng_handle
*handle
,
1341 struct lttng_calibrate
*calibrate
)
1343 struct lttcomm_session_msg lsm
;
1345 /* Safety check. NULL pointer are forbidden */
1346 if (handle
== NULL
|| calibrate
== NULL
) {
1347 return -LTTNG_ERR_INVALID
;
1350 memset(&lsm
, 0, sizeof(lsm
));
1351 lsm
.cmd_type
= LTTNG_CALIBRATE
;
1352 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1354 memcpy(&lsm
.u
.calibrate
, calibrate
, sizeof(lsm
.u
.calibrate
));
1356 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1360 * Set default channel attributes.
1361 * If either or both of the arguments are null, attr content is zeroe'd.
1363 void lttng_channel_set_default_attr(struct lttng_domain
*domain
,
1364 struct lttng_channel_attr
*attr
)
1367 if (attr
== NULL
|| domain
== NULL
) {
1371 memset(attr
, 0, sizeof(struct lttng_channel_attr
));
1373 /* Same for all domains. */
1374 attr
->overwrite
= DEFAULT_CHANNEL_OVERWRITE
;
1375 attr
->tracefile_size
= DEFAULT_CHANNEL_TRACEFILE_SIZE
;
1376 attr
->tracefile_count
= DEFAULT_CHANNEL_TRACEFILE_COUNT
;
1378 switch (domain
->type
) {
1379 case LTTNG_DOMAIN_KERNEL
:
1380 attr
->switch_timer_interval
= DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER
;
1381 attr
->read_timer_interval
= DEFAULT_KERNEL_CHANNEL_READ_TIMER
;
1382 attr
->subbuf_size
= default_get_kernel_channel_subbuf_size();
1383 attr
->num_subbuf
= DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM
;
1384 attr
->output
= DEFAULT_KERNEL_CHANNEL_OUTPUT
;
1386 case LTTNG_DOMAIN_UST
:
1387 switch (domain
->buf_type
) {
1388 case LTTNG_BUFFER_PER_UID
:
1389 attr
->subbuf_size
= default_get_ust_uid_channel_subbuf_size();
1390 attr
->num_subbuf
= DEFAULT_UST_UID_CHANNEL_SUBBUF_NUM
;
1391 attr
->output
= DEFAULT_UST_UID_CHANNEL_OUTPUT
;
1392 attr
->switch_timer_interval
= DEFAULT_UST_UID_CHANNEL_SWITCH_TIMER
;
1393 attr
->read_timer_interval
= DEFAULT_UST_UID_CHANNEL_READ_TIMER
;
1395 case LTTNG_BUFFER_PER_PID
:
1397 attr
->subbuf_size
= default_get_ust_pid_channel_subbuf_size();
1398 attr
->num_subbuf
= DEFAULT_UST_PID_CHANNEL_SUBBUF_NUM
;
1399 attr
->output
= DEFAULT_UST_PID_CHANNEL_OUTPUT
;
1400 attr
->switch_timer_interval
= DEFAULT_UST_PID_CHANNEL_SWITCH_TIMER
;
1401 attr
->read_timer_interval
= DEFAULT_UST_PID_CHANNEL_READ_TIMER
;
1405 /* Default behavior: leave set to 0. */
1411 * Check if session daemon is alive.
1413 * Return 1 if alive or 0 if not.
1414 * On error returns a negative value.
1416 int lttng_session_daemon_alive(void)
1420 ret
= set_session_daemon_path();
1426 if (*sessiond_sock_path
== '\0') {
1428 * No socket path set. Weird error which means the constructor was not
1434 ret
= try_connect_sessiond(sessiond_sock_path
);
1445 * Set URL for a consumer for a session and domain.
1447 * Return 0 on success, else a negative value.
1449 int lttng_set_consumer_url(struct lttng_handle
*handle
,
1450 const char *control_url
, const char *data_url
)
1454 struct lttcomm_session_msg lsm
;
1455 struct lttng_uri
*uris
= NULL
;
1457 if (handle
== NULL
|| (control_url
== NULL
&& data_url
== NULL
)) {
1458 return -LTTNG_ERR_INVALID
;
1461 memset(&lsm
, 0, sizeof(lsm
));
1463 lsm
.cmd_type
= LTTNG_SET_CONSUMER_URI
;
1465 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1466 sizeof(lsm
.session
.name
));
1467 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1469 size
= uri_parse_str_urls(control_url
, data_url
, &uris
);
1471 return -LTTNG_ERR_INVALID
;
1474 lsm
.u
.uri
.size
= size
;
1476 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1477 sizeof(struct lttng_uri
) * size
, NULL
);
1486 int lttng_enable_consumer(struct lttng_handle
*handle
)
1494 int lttng_disable_consumer(struct lttng_handle
*handle
)
1500 * This is an extension of create session that is ONLY and SHOULD only be used
1501 * by the lttng command line program. It exists to avoid using URI parsing in
1504 * We need the date and time for the trace path subdirectory for the case where
1505 * the user does NOT define one using either -o or -U. Using the normal
1506 * lttng_create_session API call, we have no clue on the session daemon side if
1507 * the URL was generated automatically by the client or define by the user.
1509 * So this function "wrapper" is hidden from the public API, takes the datetime
1510 * string and appends it if necessary to the URI subdirectory before sending it
1511 * to the session daemon.
1513 * With this extra function, the lttng_create_session call behavior is not
1514 * changed and the timestamp is appended to the URI on the session daemon side
1517 int _lttng_create_session_ext(const char *name
, const char *url
,
1518 const char *datetime
)
1522 struct lttcomm_session_msg lsm
;
1523 struct lttng_uri
*uris
= NULL
;
1525 if (name
== NULL
|| datetime
== NULL
) {
1526 return -LTTNG_ERR_INVALID
;
1529 memset(&lsm
, 0, sizeof(lsm
));
1531 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1532 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1534 /* There should never be a data URL */
1535 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1537 ret
= -LTTNG_ERR_INVALID
;
1541 lsm
.u
.uri
.size
= size
;
1543 if (size
> 0 && uris
[0].dtype
!= LTTNG_DST_PATH
&& strlen(uris
[0].subdir
) == 0) {
1544 /* Don't append datetime if the name was automatically created. */
1545 if (strncmp(name
, DEFAULT_SESSION_NAME
"-",
1546 strlen(DEFAULT_SESSION_NAME
) + 1)) {
1547 ret
= snprintf(uris
[0].subdir
, sizeof(uris
[0].subdir
), "%s-%s",
1550 ret
= snprintf(uris
[0].subdir
, sizeof(uris
[0].subdir
), "%s", name
);
1553 PERROR("snprintf uri subdir");
1554 ret
= -LTTNG_ERR_FATAL
;
1559 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1560 sizeof(struct lttng_uri
) * size
, NULL
);
1568 * For a given session name, this call checks if the data is ready to be read
1569 * or is still being extracted by the consumer(s) hence not ready to be used by
1572 int lttng_data_pending(const char *session_name
)
1575 struct lttcomm_session_msg lsm
;
1577 if (session_name
== NULL
) {
1578 return -LTTNG_ERR_INVALID
;
1581 memset(&lsm
, 0, sizeof(lsm
));
1582 lsm
.cmd_type
= LTTNG_DATA_PENDING
;
1584 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1585 sizeof(lsm
.session
.name
));
1587 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
1590 * The lttng_ctl_ask_sessiond function negate the return code if it's not
1591 * LTTNG_OK so getting -1 means that the reply ret_code was 1 thus meaning
1592 * that the data is available. Yes it is hackish but for now this is the
1603 * Create a session exclusively used for snapshot.
1605 * Returns LTTNG_OK on success or a negative error code.
1607 int lttng_create_session_snapshot(const char *name
, const char *snapshot_url
)
1611 struct lttcomm_session_msg lsm
;
1612 struct lttng_uri
*uris
= NULL
;
1615 return -LTTNG_ERR_INVALID
;
1618 memset(&lsm
, 0, sizeof(lsm
));
1620 lsm
.cmd_type
= LTTNG_CREATE_SESSION_SNAPSHOT
;
1621 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1623 size
= uri_parse_str_urls(snapshot_url
, NULL
, &uris
);
1625 return -LTTNG_ERR_INVALID
;
1628 lsm
.u
.uri
.size
= size
;
1630 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1631 sizeof(struct lttng_uri
) * size
, NULL
);
1638 * Create a session exclusively used for live.
1640 * Returns LTTNG_OK on success or a negative error code.
1642 int lttng_create_session_live(const char *name
, const char *url
,
1643 unsigned int timer_interval
)
1647 struct lttcomm_session_msg lsm
;
1648 struct lttng_uri
*uris
= NULL
;
1651 return -LTTNG_ERR_INVALID
;
1654 memset(&lsm
, 0, sizeof(lsm
));
1656 lsm
.cmd_type
= LTTNG_CREATE_SESSION_LIVE
;
1657 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1660 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1662 ret
= -LTTNG_ERR_INVALID
;
1666 /* file:// is not accepted for live session. */
1667 if (uris
[0].dtype
== LTTNG_DST_PATH
) {
1668 ret
= -LTTNG_ERR_INVALID
;
1675 lsm
.u
.session_live
.nb_uri
= size
;
1676 lsm
.u
.session_live
.timer_interval
= timer_interval
;
1678 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1679 sizeof(struct lttng_uri
) * size
, NULL
);
1689 static void __attribute__((constructor
)) init()
1691 /* Set default session group */
1692 lttng_set_tracing_group(DEFAULT_TRACING_GROUP
);
1698 static void __attribute__((destructor
)) lttng_ctl_exit()
1700 free(tracing_group
);