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>
38 #include "filter/filter-ast.h"
39 #include "filter/filter-parser.h"
40 #include "filter/filter-bytecode.h"
41 #include "filter/memstream.h"
42 #include "lttng-ctl-helper.h"
45 static const int print_xml
= 1;
46 #define dbg_printf(fmt, args...) \
47 printf("[debug liblttng-ctl] " fmt, ## args)
49 static const int print_xml
= 0;
50 #define dbg_printf(fmt, args...) \
52 /* do nothing but check printf format */ \
54 printf("[debug liblttnctl] " fmt, ## args); \
59 /* Socket to session daemon for communication */
60 static int sessiond_socket
;
61 static char sessiond_sock_path
[PATH_MAX
];
62 static char health_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 memcpy(dst
, src
, sizeof(struct lttng_domain
));
109 memset(dst
, 0, sizeof(struct lttng_domain
));
116 * Send lttcomm_session_msg to the session daemon.
118 * On success, returns the number of bytes sent (>=0)
119 * On error, returns -1
121 static int send_session_msg(struct lttcomm_session_msg
*lsm
)
126 ret
= -LTTNG_ERR_NO_SESSIOND
;
130 DBG("LSM cmd type : %d", lsm
->cmd_type
);
132 ret
= lttcomm_send_creds_unix_sock(sessiond_socket
, lsm
,
133 sizeof(struct lttcomm_session_msg
));
135 ret
= -LTTNG_ERR_FATAL
;
143 * Send var len data to the session daemon.
145 * On success, returns the number of bytes sent (>=0)
146 * On error, returns -1
148 static int send_session_varlen(void *data
, size_t len
)
153 ret
= -LTTNG_ERR_NO_SESSIOND
;
162 ret
= lttcomm_send_unix_sock(sessiond_socket
, data
, len
);
164 ret
= -LTTNG_ERR_FATAL
;
172 * Receive data from the sessiond socket.
174 * On success, returns the number of bytes received (>=0)
175 * On error, returns -1 (recvmsg() error) or -ENOTCONN
177 static int recv_data_sessiond(void *buf
, size_t len
)
182 ret
= -LTTNG_ERR_NO_SESSIOND
;
186 ret
= lttcomm_recv_unix_sock(sessiond_socket
, buf
, len
);
188 ret
= -LTTNG_ERR_FATAL
;
196 * Check if we are in the specified group.
198 * If yes return 1, else return -1.
200 static int check_tracing_group(const char *grp_name
)
202 struct group
*grp_tracing
; /* no free(). See getgrnam(3) */
204 int grp_list_size
, grp_id
, i
;
207 /* Get GID of group 'tracing' */
208 grp_tracing
= getgrnam(grp_name
);
210 /* If grp_tracing is NULL, the group does not exist. */
214 /* Get number of supplementary group IDs */
215 grp_list_size
= getgroups(0, NULL
);
216 if (grp_list_size
< 0) {
221 /* Alloc group list of the right size */
222 grp_list
= malloc(grp_list_size
* sizeof(gid_t
));
227 grp_id
= getgroups(grp_list_size
, grp_list
);
233 for (i
= 0; i
< grp_list_size
; i
++) {
234 if (grp_list
[i
] == grp_tracing
->gr_gid
) {
248 * Try connect to session daemon with sock_path.
250 * Return 0 on success, else -1
252 static int try_connect_sessiond(const char *sock_path
)
256 /* If socket exist, we check if the daemon listens for connect. */
257 ret
= access(sock_path
, F_OK
);
263 ret
= lttcomm_connect_unix_sock(sock_path
);
269 ret
= lttcomm_close_unix_sock(ret
);
271 perror("lttcomm_close_unix_sock");
281 * Set sessiond socket path by putting it in the global sessiond_sock_path
284 * Returns 0 on success, negative value on failure (the sessiond socket path
285 * is somehow too long or ENOMEM).
287 static int set_session_daemon_path(void)
289 int in_tgroup
= 0; /* In tracing group */
295 /* Are we in the tracing group ? */
296 in_tgroup
= check_tracing_group(tracing_group
);
299 if ((uid
== 0) || in_tgroup
) {
300 lttng_ctl_copy_string(sessiond_sock_path
,
301 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK
, sizeof(sessiond_sock_path
));
309 ret
= try_connect_sessiond(sessiond_sock_path
);
313 /* Global session daemon not available... */
315 /* ...or not in tracing group (and not root), default */
318 * With GNU C < 2.1, snprintf returns -1 if the target buffer is too small;
319 * With GNU C >= 2.1, snprintf returns the required size (excluding closing null)
321 ret
= snprintf(sessiond_sock_path
, sizeof(sessiond_sock_path
),
322 DEFAULT_HOME_CLIENT_UNIX_SOCK
, utils_get_home_dir());
323 if ((ret
< 0) || (ret
>= sizeof(sessiond_sock_path
))) {
335 * Connect to the LTTng session daemon.
337 * On success, return 0. On error, return -1.
339 static int connect_sessiond(void)
343 /* Don't try to connect if already connected. */
348 ret
= set_session_daemon_path();
353 /* Connect to the sesssion daemon */
354 ret
= lttcomm_connect_unix_sock(sessiond_sock_path
);
359 sessiond_socket
= ret
;
369 * Clean disconnect from the session daemon.
370 * On success, return 0. On error, return -1.
372 static int disconnect_sessiond(void)
377 ret
= lttcomm_close_unix_sock(sessiond_socket
);
386 * Ask the session daemon a specific command and put the data into buf.
387 * Takes extra var. len. data as input to send to the session daemon.
389 * Return size of data (only payload, not header) or a negative error code.
392 int lttng_ctl_ask_sessiond_varlen(struct lttcomm_session_msg
*lsm
,
393 void *vardata
, size_t varlen
, void **buf
)
398 struct lttcomm_lttng_msg llm
;
400 ret
= connect_sessiond();
402 ret
= -LTTNG_ERR_NO_SESSIOND
;
406 /* Send command to session daemon */
407 ret
= send_session_msg(lsm
);
409 /* Ret value is a valid lttng error code. */
412 /* Send var len data */
413 ret
= send_session_varlen(vardata
, varlen
);
415 /* Ret value is a valid lttng error code. */
419 /* Get header from data transmission */
420 ret
= recv_data_sessiond(&llm
, sizeof(llm
));
422 /* Ret value is a valid lttng error code. */
426 /* Check error code if OK */
427 if (llm
.ret_code
!= LTTNG_OK
) {
432 size
= llm
.data_size
;
434 /* If client free with size 0 */
442 data
= (void*) malloc(size
);
444 /* Get payload data */
445 ret
= recv_data_sessiond(data
, size
);
452 * Extra protection not to dereference a NULL pointer. If buf is NULL at
453 * this point, an error is returned and data is freed.
456 ret
= -LTTNG_ERR_INVALID
;
465 disconnect_sessiond();
470 * Create lttng handle and return pointer.
471 * The returned pointer will be NULL in case of malloc() error.
473 struct lttng_handle
*lttng_create_handle(const char *session_name
,
474 struct lttng_domain
*domain
)
476 struct lttng_handle
*handle
= NULL
;
478 if (domain
== NULL
) {
482 handle
= malloc(sizeof(struct lttng_handle
));
483 if (handle
== NULL
) {
484 PERROR("malloc handle");
488 /* Copy session name */
489 lttng_ctl_copy_string(handle
->session_name
, session_name
,
490 sizeof(handle
->session_name
));
492 /* Copy lttng domain */
493 lttng_ctl_copy_lttng_domain(&handle
->domain
, domain
);
500 * Destroy handle by free(3) the pointer.
502 void lttng_destroy_handle(struct lttng_handle
*handle
)
508 * Register an outside consumer.
509 * Returns size of returned session payload data or a negative error code.
511 int lttng_register_consumer(struct lttng_handle
*handle
,
512 const char *socket_path
)
514 struct lttcomm_session_msg lsm
;
516 if (handle
== NULL
|| socket_path
== NULL
) {
517 return -LTTNG_ERR_INVALID
;
520 lsm
.cmd_type
= LTTNG_REGISTER_CONSUMER
;
521 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
522 sizeof(lsm
.session
.name
));
523 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
525 lttng_ctl_copy_string(lsm
.u
.reg
.path
, socket_path
, sizeof(lsm
.u
.reg
.path
));
527 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
531 * Start tracing for all traces of the session.
532 * Returns size of returned session payload data or a negative error code.
534 int lttng_start_tracing(const char *session_name
)
536 struct lttcomm_session_msg lsm
;
538 if (session_name
== NULL
) {
539 return -LTTNG_ERR_INVALID
;
542 lsm
.cmd_type
= LTTNG_START_TRACE
;
544 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
545 sizeof(lsm
.session
.name
));
547 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
551 * Stop tracing for all traces of the session.
553 static int _lttng_stop_tracing(const char *session_name
, int wait
)
556 struct lttcomm_session_msg lsm
;
558 if (session_name
== NULL
) {
559 return -LTTNG_ERR_INVALID
;
562 lsm
.cmd_type
= LTTNG_STOP_TRACE
;
564 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
565 sizeof(lsm
.session
.name
));
567 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
568 if (ret
< 0 && ret
!= -LTTNG_ERR_TRACE_ALREADY_STOPPED
) {
576 _MSG("Waiting for data availability");
578 /* Check for data availability */
580 data_ret
= lttng_data_pending(session_name
);
582 /* Return the data available call error. */
588 * Data sleep time before retrying (in usec). Don't sleep if the call
589 * returned value indicates availability.
592 usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME
);
595 } while (data_ret
!= 0);
605 * Stop tracing and wait for data availability.
607 int lttng_stop_tracing(const char *session_name
)
609 return _lttng_stop_tracing(session_name
, 1);
613 * Stop tracing but _don't_ wait for data availability.
615 int lttng_stop_tracing_no_wait(const char *session_name
)
617 return _lttng_stop_tracing(session_name
, 0);
621 * Add context to a channel.
623 * If the given channel is NULL, add the contexts to all channels.
624 * The event_name param is ignored.
626 * Returns the size of the returned payload data or a negative error code.
628 int lttng_add_context(struct lttng_handle
*handle
,
629 struct lttng_event_context
*ctx
, const char *event_name
,
630 const char *channel_name
)
632 struct lttcomm_session_msg lsm
;
634 /* Safety check. Both are mandatory */
635 if (handle
== NULL
|| ctx
== NULL
) {
636 return -LTTNG_ERR_INVALID
;
639 memset(&lsm
, 0, sizeof(lsm
));
641 lsm
.cmd_type
= LTTNG_ADD_CONTEXT
;
643 /* Copy channel name */
644 lttng_ctl_copy_string(lsm
.u
.context
.channel_name
, channel_name
,
645 sizeof(lsm
.u
.context
.channel_name
));
647 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
649 memcpy(&lsm
.u
.context
.ctx
, ctx
, sizeof(struct lttng_event_context
));
651 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
652 sizeof(lsm
.session
.name
));
654 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
658 * Enable event(s) for a channel.
659 * If no event name is specified, all events are enabled.
660 * If no channel name is specified, the default 'channel0' is used.
661 * Returns size of returned session payload data or a negative error code.
663 int lttng_enable_event(struct lttng_handle
*handle
,
664 struct lttng_event
*ev
, const char *channel_name
)
666 struct lttcomm_session_msg lsm
;
668 if (handle
== NULL
|| ev
== NULL
) {
669 return -LTTNG_ERR_INVALID
;
672 memset(&lsm
, 0, sizeof(lsm
));
674 /* If no channel name, we put the default name */
675 if (channel_name
== NULL
) {
676 lttng_ctl_copy_string(lsm
.u
.enable
.channel_name
, DEFAULT_CHANNEL_NAME
,
677 sizeof(lsm
.u
.enable
.channel_name
));
679 lttng_ctl_copy_string(lsm
.u
.enable
.channel_name
, channel_name
,
680 sizeof(lsm
.u
.enable
.channel_name
));
683 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
685 if (ev
->name
[0] != '\0') {
686 lsm
.cmd_type
= LTTNG_ENABLE_EVENT
;
688 lsm
.cmd_type
= LTTNG_ENABLE_ALL_EVENT
;
690 memcpy(&lsm
.u
.enable
.event
, ev
, sizeof(lsm
.u
.enable
.event
));
692 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
693 sizeof(lsm
.session
.name
));
695 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
699 * Create or enable an event with a filter expression.
701 * Return negative error value on error.
702 * Return size of returned session payload data if OK.
704 int lttng_enable_event_with_filter(struct lttng_handle
*handle
,
705 struct lttng_event
*event
, const char *channel_name
,
706 const char *filter_expression
)
708 struct lttcomm_session_msg lsm
;
709 struct filter_parser_ctx
*ctx
;
713 if (!filter_expression
) {
715 * Fall back to normal event enabling if no filter
718 return lttng_enable_event(handle
, event
, channel_name
);
722 * Empty filter string will always be rejected by the parser
723 * anyway, so treat this corner-case early to eliminate
724 * lttng_fmemopen error for 0-byte allocation.
726 if (handle
== NULL
|| filter_expression
[0] == '\0') {
727 return -LTTNG_ERR_INVALID
;
731 * casting const to non-const, as the underlying function will
732 * use it in read-only mode.
734 fmem
= lttng_fmemopen((void *) filter_expression
,
735 strlen(filter_expression
), "r");
737 fprintf(stderr
, "Error opening memory as stream\n");
738 return -LTTNG_ERR_FILTER_NOMEM
;
740 ctx
= filter_parser_ctx_alloc(fmem
);
742 fprintf(stderr
, "Error allocating parser\n");
743 ret
= -LTTNG_ERR_FILTER_NOMEM
;
746 ret
= filter_parser_ctx_append_ast(ctx
);
748 fprintf(stderr
, "Parse error\n");
749 ret
= -LTTNG_ERR_FILTER_INVAL
;
752 ret
= filter_visitor_set_parent(ctx
);
754 fprintf(stderr
, "Set parent error\n");
755 ret
= -LTTNG_ERR_FILTER_INVAL
;
759 ret
= filter_visitor_print_xml(ctx
, stdout
, 0);
762 fprintf(stderr
, "XML print error\n");
763 ret
= -LTTNG_ERR_FILTER_INVAL
;
768 dbg_printf("Generating IR... ");
770 ret
= filter_visitor_ir_generate(ctx
);
772 fprintf(stderr
, "Generate IR error\n");
773 ret
= -LTTNG_ERR_FILTER_INVAL
;
776 dbg_printf("done\n");
778 dbg_printf("Validating IR... ");
780 ret
= filter_visitor_ir_check_binary_op_nesting(ctx
);
782 ret
= -LTTNG_ERR_FILTER_INVAL
;
785 dbg_printf("done\n");
787 dbg_printf("Generating bytecode... ");
789 ret
= filter_visitor_bytecode_generate(ctx
);
791 fprintf(stderr
, "Generate bytecode error\n");
792 ret
= -LTTNG_ERR_FILTER_INVAL
;
795 dbg_printf("done\n");
796 dbg_printf("Size of bytecode generated: %u bytes.\n",
797 bytecode_get_len(&ctx
->bytecode
->b
));
799 memset(&lsm
, 0, sizeof(lsm
));
801 lsm
.cmd_type
= LTTNG_ENABLE_EVENT_WITH_FILTER
;
803 /* Copy channel name */
804 lttng_ctl_copy_string(lsm
.u
.enable
.channel_name
, channel_name
,
805 sizeof(lsm
.u
.enable
.channel_name
));
806 /* Copy event name */
808 memcpy(&lsm
.u
.enable
.event
, event
, sizeof(lsm
.u
.enable
.event
));
811 lsm
.u
.enable
.bytecode_len
= sizeof(ctx
->bytecode
->b
)
812 + bytecode_get_len(&ctx
->bytecode
->b
);
814 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
816 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
817 sizeof(lsm
.session
.name
));
819 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, &ctx
->bytecode
->b
,
820 lsm
.u
.enable
.bytecode_len
, NULL
);
822 filter_bytecode_free(ctx
);
824 filter_parser_ctx_free(ctx
);
825 if (fclose(fmem
) != 0) {
831 filter_bytecode_free(ctx
);
833 filter_parser_ctx_free(ctx
);
835 if (fclose(fmem
) != 0) {
842 * Disable event(s) of a channel and domain.
843 * If no event name is specified, all events are disabled.
844 * If no channel name is specified, the default 'channel0' is used.
845 * Returns size of returned session payload data or a negative error code.
847 int lttng_disable_event(struct lttng_handle
*handle
, const char *name
,
848 const char *channel_name
)
850 struct lttcomm_session_msg lsm
;
852 if (handle
== NULL
) {
853 return -LTTNG_ERR_INVALID
;
856 memset(&lsm
, 0, sizeof(lsm
));
859 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, channel_name
,
860 sizeof(lsm
.u
.disable
.channel_name
));
862 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, DEFAULT_CHANNEL_NAME
,
863 sizeof(lsm
.u
.disable
.channel_name
));
866 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
869 lttng_ctl_copy_string(lsm
.u
.disable
.name
, name
,
870 sizeof(lsm
.u
.disable
.name
));
871 lsm
.cmd_type
= LTTNG_DISABLE_EVENT
;
873 lsm
.cmd_type
= LTTNG_DISABLE_ALL_EVENT
;
876 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
877 sizeof(lsm
.session
.name
));
879 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
883 * Enable channel per domain
884 * Returns size of returned session payload data or a negative error code.
886 int lttng_enable_channel(struct lttng_handle
*handle
,
887 struct lttng_channel
*chan
)
889 struct lttcomm_session_msg lsm
;
892 * NULL arguments are forbidden. No default values.
894 if (handle
== NULL
|| chan
== NULL
) {
895 return -LTTNG_ERR_INVALID
;
898 memset(&lsm
, 0, sizeof(lsm
));
900 memcpy(&lsm
.u
.channel
.chan
, chan
, sizeof(lsm
.u
.channel
.chan
));
902 lsm
.cmd_type
= LTTNG_ENABLE_CHANNEL
;
904 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
906 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
907 sizeof(lsm
.session
.name
));
909 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
913 * All tracing will be stopped for registered events of the channel.
914 * Returns size of returned session payload data or a negative error code.
916 int lttng_disable_channel(struct lttng_handle
*handle
, const char *name
)
918 struct lttcomm_session_msg lsm
;
920 /* Safety check. Both are mandatory */
921 if (handle
== NULL
|| name
== NULL
) {
922 return -LTTNG_ERR_INVALID
;
925 memset(&lsm
, 0, sizeof(lsm
));
927 lsm
.cmd_type
= LTTNG_DISABLE_CHANNEL
;
929 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, name
,
930 sizeof(lsm
.u
.disable
.channel_name
));
932 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
934 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
935 sizeof(lsm
.session
.name
));
937 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
941 * Lists all available tracepoints of domain.
942 * Sets the contents of the events array.
943 * Returns the number of lttng_event entries in events;
944 * on error, returns a negative value.
946 int lttng_list_tracepoints(struct lttng_handle
*handle
,
947 struct lttng_event
**events
)
950 struct lttcomm_session_msg lsm
;
952 if (handle
== NULL
) {
953 return -LTTNG_ERR_INVALID
;
956 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINTS
;
957 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
959 ret
= lttng_ctl_ask_sessiond(&lsm
, (void **) events
);
964 return ret
/ sizeof(struct lttng_event
);
968 * Lists all available tracepoint fields of domain.
969 * Sets the contents of the event field array.
970 * Returns the number of lttng_event_field entries in events;
971 * on error, returns a negative value.
973 int lttng_list_tracepoint_fields(struct lttng_handle
*handle
,
974 struct lttng_event_field
**fields
)
977 struct lttcomm_session_msg lsm
;
979 if (handle
== NULL
) {
980 return -LTTNG_ERR_INVALID
;
983 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINT_FIELDS
;
984 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
986 ret
= lttng_ctl_ask_sessiond(&lsm
, (void **) fields
);
991 return ret
/ sizeof(struct lttng_event_field
);
995 * Returns a human readable string describing
996 * the error code (a negative value).
998 const char *lttng_strerror(int code
)
1000 return error_get_str(code
);
1004 * Create a brand new session using name and url for destination.
1006 * Returns LTTNG_OK on success or a negative error code.
1008 int lttng_create_session(const char *name
, const char *url
)
1012 struct lttcomm_session_msg lsm
;
1013 struct lttng_uri
*uris
= NULL
;
1016 return -LTTNG_ERR_INVALID
;
1019 memset(&lsm
, 0, sizeof(lsm
));
1021 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1022 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1024 /* There should never be a data URL */
1025 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1027 return -LTTNG_ERR_INVALID
;
1030 lsm
.u
.uri
.size
= size
;
1032 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1033 sizeof(struct lttng_uri
) * size
, NULL
);
1040 * Destroy session using name.
1041 * Returns size of returned session payload data or a negative error code.
1043 int lttng_destroy_session(const char *session_name
)
1045 struct lttcomm_session_msg lsm
;
1047 if (session_name
== NULL
) {
1048 return -LTTNG_ERR_INVALID
;
1051 lsm
.cmd_type
= LTTNG_DESTROY_SESSION
;
1053 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1054 sizeof(lsm
.session
.name
));
1056 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1060 * Ask the session daemon for all available sessions.
1061 * Sets the contents of the sessions array.
1062 * Returns the number of lttng_session entries in sessions;
1063 * on error, returns a negative value.
1065 int lttng_list_sessions(struct lttng_session
**sessions
)
1068 struct lttcomm_session_msg lsm
;
1070 lsm
.cmd_type
= LTTNG_LIST_SESSIONS
;
1071 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) sessions
);
1076 return ret
/ sizeof(struct lttng_session
);
1080 * Ask the session daemon for all available domains of a session.
1081 * Sets the contents of the domains array.
1082 * Returns the number of lttng_domain entries in domains;
1083 * on error, returns a negative value.
1085 int lttng_list_domains(const char *session_name
,
1086 struct lttng_domain
**domains
)
1089 struct lttcomm_session_msg lsm
;
1091 if (session_name
== NULL
) {
1092 return -LTTNG_ERR_INVALID
;
1095 lsm
.cmd_type
= LTTNG_LIST_DOMAINS
;
1097 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1098 sizeof(lsm
.session
.name
));
1100 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) domains
);
1105 return ret
/ sizeof(struct lttng_domain
);
1109 * Ask the session daemon for all available channels of a session.
1110 * Sets the contents of the channels array.
1111 * Returns the number of lttng_channel entries in channels;
1112 * on error, returns a negative value.
1114 int lttng_list_channels(struct lttng_handle
*handle
,
1115 struct lttng_channel
**channels
)
1118 struct lttcomm_session_msg lsm
;
1120 if (handle
== NULL
) {
1121 return -LTTNG_ERR_INVALID
;
1124 lsm
.cmd_type
= LTTNG_LIST_CHANNELS
;
1125 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1126 sizeof(lsm
.session
.name
));
1128 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1130 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) channels
);
1135 return ret
/ sizeof(struct lttng_channel
);
1139 * Ask the session daemon for all available events of a session channel.
1140 * Sets the contents of the events array.
1141 * Returns the number of lttng_event entries in events;
1142 * on error, returns a negative value.
1144 int lttng_list_events(struct lttng_handle
*handle
,
1145 const char *channel_name
, struct lttng_event
**events
)
1148 struct lttcomm_session_msg lsm
;
1150 /* Safety check. An handle and channel name are mandatory */
1151 if (handle
== NULL
|| channel_name
== NULL
) {
1152 return -LTTNG_ERR_INVALID
;
1155 lsm
.cmd_type
= LTTNG_LIST_EVENTS
;
1156 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1157 sizeof(lsm
.session
.name
));
1158 lttng_ctl_copy_string(lsm
.u
.list
.channel_name
, channel_name
,
1159 sizeof(lsm
.u
.list
.channel_name
));
1161 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1163 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) events
);
1168 return ret
/ sizeof(struct lttng_event
);
1172 * Sets the tracing_group variable with name.
1173 * This function allocates memory pointed to by tracing_group.
1174 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
1176 int lttng_set_tracing_group(const char *name
)
1179 return -LTTNG_ERR_INVALID
;
1182 if (asprintf(&tracing_group
, "%s", name
) < 0) {
1183 return -LTTNG_ERR_FATAL
;
1190 * Returns size of returned session payload data or a negative error code.
1192 int lttng_calibrate(struct lttng_handle
*handle
,
1193 struct lttng_calibrate
*calibrate
)
1195 struct lttcomm_session_msg lsm
;
1197 /* Safety check. NULL pointer are forbidden */
1198 if (handle
== NULL
|| calibrate
== NULL
) {
1199 return -LTTNG_ERR_INVALID
;
1202 lsm
.cmd_type
= LTTNG_CALIBRATE
;
1203 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1205 memcpy(&lsm
.u
.calibrate
, calibrate
, sizeof(lsm
.u
.calibrate
));
1207 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1211 * Set default channel attributes.
1212 * If either or both of the arguments are null, attr content is zeroe'd.
1214 void lttng_channel_set_default_attr(struct lttng_domain
*domain
,
1215 struct lttng_channel_attr
*attr
)
1218 if (attr
== NULL
|| domain
== NULL
) {
1222 memset(attr
, 0, sizeof(struct lttng_channel_attr
));
1224 /* Same for all domains. */
1225 attr
->overwrite
= DEFAULT_CHANNEL_OVERWRITE
;
1226 attr
->tracefile_size
= DEFAULT_CHANNEL_TRACEFILE_SIZE
;
1227 attr
->tracefile_count
= DEFAULT_CHANNEL_TRACEFILE_COUNT
;
1229 switch (domain
->type
) {
1230 case LTTNG_DOMAIN_KERNEL
:
1231 attr
->switch_timer_interval
= DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER
;
1232 attr
->read_timer_interval
= DEFAULT_KERNEL_CHANNEL_READ_TIMER
;
1233 attr
->subbuf_size
= default_get_kernel_channel_subbuf_size();
1234 attr
->num_subbuf
= DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM
;
1235 attr
->output
= DEFAULT_KERNEL_CHANNEL_OUTPUT
;
1237 case LTTNG_DOMAIN_UST
:
1238 switch (domain
->buf_type
) {
1239 case LTTNG_BUFFER_PER_UID
:
1240 attr
->subbuf_size
= default_get_ust_uid_channel_subbuf_size();
1241 attr
->num_subbuf
= DEFAULT_UST_UID_CHANNEL_SUBBUF_NUM
;
1242 attr
->output
= DEFAULT_UST_UID_CHANNEL_OUTPUT
;
1243 attr
->switch_timer_interval
= DEFAULT_UST_UID_CHANNEL_SWITCH_TIMER
;
1244 attr
->read_timer_interval
= DEFAULT_UST_UID_CHANNEL_READ_TIMER
;
1246 case LTTNG_BUFFER_PER_PID
:
1248 attr
->subbuf_size
= default_get_ust_pid_channel_subbuf_size();
1249 attr
->num_subbuf
= DEFAULT_UST_PID_CHANNEL_SUBBUF_NUM
;
1250 attr
->output
= DEFAULT_UST_PID_CHANNEL_OUTPUT
;
1251 attr
->switch_timer_interval
= DEFAULT_UST_PID_CHANNEL_SWITCH_TIMER
;
1252 attr
->read_timer_interval
= DEFAULT_UST_PID_CHANNEL_READ_TIMER
;
1256 /* Default behavior: leave set to 0. */
1262 * Check if session daemon is alive.
1264 * Return 1 if alive or 0 if not.
1265 * On error returns a negative value.
1267 int lttng_session_daemon_alive(void)
1271 ret
= set_session_daemon_path();
1277 if (*sessiond_sock_path
== '\0') {
1279 * No socket path set. Weird error which means the constructor was not
1285 ret
= try_connect_sessiond(sessiond_sock_path
);
1296 * Set URL for a consumer for a session and domain.
1298 * Return 0 on success, else a negative value.
1300 int lttng_set_consumer_url(struct lttng_handle
*handle
,
1301 const char *control_url
, const char *data_url
)
1305 struct lttcomm_session_msg lsm
;
1306 struct lttng_uri
*uris
= NULL
;
1308 if (handle
== NULL
|| (control_url
== NULL
&& data_url
== NULL
)) {
1309 return -LTTNG_ERR_INVALID
;
1312 memset(&lsm
, 0, sizeof(lsm
));
1314 lsm
.cmd_type
= LTTNG_SET_CONSUMER_URI
;
1316 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1317 sizeof(lsm
.session
.name
));
1318 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1320 size
= uri_parse_str_urls(control_url
, data_url
, &uris
);
1322 return -LTTNG_ERR_INVALID
;
1325 lsm
.u
.uri
.size
= size
;
1327 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1328 sizeof(struct lttng_uri
) * size
, NULL
);
1337 int lttng_enable_consumer(struct lttng_handle
*handle
)
1345 int lttng_disable_consumer(struct lttng_handle
*handle
)
1351 * Set health socket path by putting it in the global health_sock_path
1354 * Returns 0 on success or assert(0) on ENOMEM.
1356 static int set_health_socket_path(void)
1358 int in_tgroup
= 0; /* In tracing group */
1365 /* Are we in the tracing group ? */
1366 in_tgroup
= check_tracing_group(tracing_group
);
1369 if ((uid
== 0) || in_tgroup
) {
1370 lttng_ctl_copy_string(health_sock_path
,
1371 DEFAULT_GLOBAL_HEALTH_UNIX_SOCK
, sizeof(health_sock_path
));
1378 * With GNU C < 2.1, snprintf returns -1 if the target buffer is too small;
1379 * With GNU C >= 2.1, snprintf returns the required size (excluding closing null)
1381 home
= utils_get_home_dir();
1383 /* Fallback in /tmp .. */
1387 ret
= snprintf(health_sock_path
, sizeof(health_sock_path
),
1388 DEFAULT_HOME_HEALTH_UNIX_SOCK
, home
);
1389 if ((ret
< 0) || (ret
>= sizeof(health_sock_path
))) {
1390 /* ENOMEM at this point... just kill the control lib. */
1399 * Check session daemon health for a specific health component.
1401 * Return 0 if health is OK or else 1 if BAD.
1403 * Any other negative value is a lttng error code which can be translated with
1406 int lttng_health_check(enum lttng_health_component c
)
1409 struct lttcomm_health_msg msg
;
1410 struct lttcomm_health_data reply
;
1412 /* Connect to the sesssion daemon */
1413 sock
= lttcomm_connect_unix_sock(health_sock_path
);
1415 ret
= -LTTNG_ERR_NO_SESSIOND
;
1419 msg
.cmd
= LTTNG_HEALTH_CHECK
;
1422 ret
= lttcomm_send_unix_sock(sock
, (void *)&msg
, sizeof(msg
));
1424 ret
= -LTTNG_ERR_FATAL
;
1428 ret
= lttcomm_recv_unix_sock(sock
, (void *)&reply
, sizeof(reply
));
1430 ret
= -LTTNG_ERR_FATAL
;
1434 ret
= reply
.ret_code
;
1440 closeret
= close(sock
);
1449 * This is an extension of create session that is ONLY and SHOULD only be used
1450 * by the lttng command line program. It exists to avoid using URI parsing in
1453 * We need the date and time for the trace path subdirectory for the case where
1454 * the user does NOT define one using either -o or -U. Using the normal
1455 * lttng_create_session API call, we have no clue on the session daemon side if
1456 * the URL was generated automatically by the client or define by the user.
1458 * So this function "wrapper" is hidden from the public API, takes the datetime
1459 * string and appends it if necessary to the URI subdirectory before sending it
1460 * to the session daemon.
1462 * With this extra function, the lttng_create_session call behavior is not
1463 * changed and the timestamp is appended to the URI on the session daemon side
1466 int _lttng_create_session_ext(const char *name
, const char *url
,
1467 const char *datetime
)
1471 struct lttcomm_session_msg lsm
;
1472 struct lttng_uri
*uris
= NULL
;
1474 if (name
== NULL
|| datetime
== NULL
|| url
== NULL
) {
1475 return -LTTNG_ERR_INVALID
;
1478 memset(&lsm
, 0, sizeof(lsm
));
1480 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1481 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1483 /* There should never be a data URL */
1484 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1486 ret
= -LTTNG_ERR_INVALID
;
1490 lsm
.u
.uri
.size
= size
;
1492 if (size
> 0 && uris
[0].dtype
!= LTTNG_DST_PATH
&& strlen(uris
[0].subdir
) == 0) {
1493 /* Don't append datetime if the name was automatically created. */
1494 if (strncmp(name
, DEFAULT_SESSION_NAME
"-",
1495 strlen(DEFAULT_SESSION_NAME
) + 1)) {
1496 ret
= snprintf(uris
[0].subdir
, sizeof(uris
[0].subdir
), "%s-%s",
1499 ret
= snprintf(uris
[0].subdir
, sizeof(uris
[0].subdir
), "%s", name
);
1502 PERROR("snprintf uri subdir");
1503 ret
= -LTTNG_ERR_FATAL
;
1508 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1509 sizeof(struct lttng_uri
) * size
, NULL
);
1517 * For a given session name, this call checks if the data is ready to be read
1518 * or is still being extracted by the consumer(s) hence not ready to be used by
1521 int lttng_data_pending(const char *session_name
)
1524 struct lttcomm_session_msg lsm
;
1526 if (session_name
== NULL
) {
1527 return -LTTNG_ERR_INVALID
;
1530 lsm
.cmd_type
= LTTNG_DATA_PENDING
;
1532 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1533 sizeof(lsm
.session
.name
));
1535 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
1538 * The lttng_ctl_ask_sessiond function negate the return code if it's not
1539 * LTTNG_OK so getting -1 means that the reply ret_code was 1 thus meaning
1540 * that the data is available. Yes it is hackish but for now this is the
1553 static void __attribute__((constructor
)) init()
1555 /* Set default session group */
1556 lttng_set_tracing_group(DEFAULT_TRACING_GROUP
);
1557 /* Set socket for health check */
1558 (void) set_health_socket_path();
1564 static void __attribute__((destructor
)) lttng_ctl_exit()
1566 free(tracing_group
);