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 lsm
.cmd_type
= LTTNG_REGISTER_CONSUMER
;
524 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
525 sizeof(lsm
.session
.name
));
526 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
528 lttng_ctl_copy_string(lsm
.u
.reg
.path
, socket_path
, sizeof(lsm
.u
.reg
.path
));
530 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
534 * Start tracing for all traces of the session.
535 * Returns size of returned session payload data or a negative error code.
537 int lttng_start_tracing(const char *session_name
)
539 struct lttcomm_session_msg lsm
;
541 if (session_name
== NULL
) {
542 return -LTTNG_ERR_INVALID
;
545 lsm
.cmd_type
= LTTNG_START_TRACE
;
547 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
548 sizeof(lsm
.session
.name
));
550 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
554 * Stop tracing for all traces of the session.
556 static int _lttng_stop_tracing(const char *session_name
, int wait
)
559 struct lttcomm_session_msg lsm
;
561 if (session_name
== NULL
) {
562 return -LTTNG_ERR_INVALID
;
565 lsm
.cmd_type
= LTTNG_STOP_TRACE
;
567 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
568 sizeof(lsm
.session
.name
));
570 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
571 if (ret
< 0 && ret
!= -LTTNG_ERR_TRACE_ALREADY_STOPPED
) {
579 _MSG("Waiting for data availability");
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
);
600 } while (data_ret
!= 0);
610 * Stop tracing and wait for data availability.
612 int lttng_stop_tracing(const char *session_name
)
614 return _lttng_stop_tracing(session_name
, 1);
618 * Stop tracing but _don't_ wait for data availability.
620 int lttng_stop_tracing_no_wait(const char *session_name
)
622 return _lttng_stop_tracing(session_name
, 0);
626 * Add context to a channel.
628 * If the given channel is NULL, add the contexts to all channels.
629 * The event_name param is ignored.
631 * Returns the size of the returned payload data or a negative error code.
633 int lttng_add_context(struct lttng_handle
*handle
,
634 struct lttng_event_context
*ctx
, const char *event_name
,
635 const char *channel_name
)
637 struct lttcomm_session_msg lsm
;
639 /* Safety check. Both are mandatory */
640 if (handle
== NULL
|| ctx
== NULL
) {
641 return -LTTNG_ERR_INVALID
;
644 memset(&lsm
, 0, sizeof(lsm
));
646 lsm
.cmd_type
= LTTNG_ADD_CONTEXT
;
648 /* If no channel name, send empty string. */
649 if (channel_name
== NULL
) {
650 lttng_ctl_copy_string(lsm
.u
.context
.channel_name
, "",
651 sizeof(lsm
.u
.context
.channel_name
));
653 lttng_ctl_copy_string(lsm
.u
.context
.channel_name
, channel_name
,
654 sizeof(lsm
.u
.context
.channel_name
));
657 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
659 memcpy(&lsm
.u
.context
.ctx
, ctx
, sizeof(struct lttng_event_context
));
661 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
662 sizeof(lsm
.session
.name
));
664 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
668 * Enable event(s) for a channel.
669 * If no event name is specified, all events are enabled.
670 * If no channel name is specified, the default 'channel0' is used.
671 * Returns size of returned session payload data or a negative error code.
673 int lttng_enable_event(struct lttng_handle
*handle
,
674 struct lttng_event
*ev
, const char *channel_name
)
676 return lttng_enable_event_with_exclusions(handle
, ev
, channel_name
,
681 * Create or enable an event with a filter expression.
683 * Return negative error value on error.
684 * Return size of returned session payload data if OK.
686 int lttng_enable_event_with_filter(struct lttng_handle
*handle
,
687 struct lttng_event
*event
, const char *channel_name
,
688 const char *filter_expression
)
690 return lttng_enable_event_with_exclusions(handle
, event
, channel_name
,
691 filter_expression
, 0, NULL
);
695 * Enable event(s) for a channel, possibly with exclusions and a filter.
696 * If no event name is specified, all events are enabled.
697 * If no channel name is specified, the default name is used.
698 * If filter expression is not NULL, the filter is set for the event.
699 * If exclusion count is not zero, the exclusions are set for the event.
700 * Returns size of returned session payload data or a negative error code.
702 int lttng_enable_event_with_exclusions(struct lttng_handle
*handle
,
703 struct lttng_event
*ev
, const char *channel_name
,
704 const char *filter_expression
,
705 int exclusion_count
, char **exclusion_list
)
707 struct lttcomm_session_msg lsm
;
710 struct filter_parser_ctx
*ctx
= NULL
;
713 if (handle
== NULL
|| ev
== NULL
) {
714 return -LTTNG_ERR_INVALID
;
717 /* Empty filter string will always be rejected by the parser
718 * anyway, so treat this corner-case early to eliminate
719 * lttng_fmemopen error for 0-byte allocation.
721 if (filter_expression
&& filter_expression
[0] == '\0') {
722 return -LTTNG_ERR_INVALID
;
725 memset(&lsm
, 0, sizeof(lsm
));
727 /* If no channel name, send empty string. */
728 if (channel_name
== NULL
) {
729 lttng_ctl_copy_string(lsm
.u
.enable
.channel_name
, "",
730 sizeof(lsm
.u
.enable
.channel_name
));
732 lttng_ctl_copy_string(lsm
.u
.enable
.channel_name
, channel_name
,
733 sizeof(lsm
.u
.enable
.channel_name
));
736 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
737 lsm
.cmd_type
= LTTNG_ENABLE_EVENT
;
739 memcpy(&lsm
.u
.enable
.event
, ev
, sizeof(lsm
.u
.enable
.event
));
741 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
742 sizeof(lsm
.session
.name
));
743 lsm
.u
.enable
.exclusion_count
= exclusion_count
;
744 lsm
.u
.enable
.bytecode_len
= 0;
746 if (exclusion_count
== 0 && filter_expression
== NULL
) {
747 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
752 * We have either a filter or some exclusions, so we need to set up
753 * a variable-length memory block from where to send the data
756 /* Parse filter expression */
757 if (filter_expression
!= NULL
) {
760 * casting const to non-const, as the underlying function will
761 * use it in read-only mode.
763 fmem
= lttng_fmemopen((void *) filter_expression
,
764 strlen(filter_expression
), "r");
766 fprintf(stderr
, "Error opening memory as stream\n");
767 return -LTTNG_ERR_FILTER_NOMEM
;
769 ctx
= filter_parser_ctx_alloc(fmem
);
771 fprintf(stderr
, "Error allocating parser\n");
772 ret
= -LTTNG_ERR_FILTER_NOMEM
;
773 goto filter_alloc_error
;
775 ret
= filter_parser_ctx_append_ast(ctx
);
777 fprintf(stderr
, "Parse error\n");
778 ret
= -LTTNG_ERR_FILTER_INVAL
;
781 ret
= filter_visitor_set_parent(ctx
);
783 fprintf(stderr
, "Set parent error\n");
784 ret
= -LTTNG_ERR_FILTER_INVAL
;
788 ret
= filter_visitor_print_xml(ctx
, stdout
, 0);
791 fprintf(stderr
, "XML print error\n");
792 ret
= -LTTNG_ERR_FILTER_INVAL
;
797 dbg_printf("Generating IR... ");
799 ret
= filter_visitor_ir_generate(ctx
);
801 fprintf(stderr
, "Generate IR error\n");
802 ret
= -LTTNG_ERR_FILTER_INVAL
;
805 dbg_printf("done\n");
807 dbg_printf("Validating IR... ");
809 ret
= filter_visitor_ir_check_binary_op_nesting(ctx
);
811 ret
= -LTTNG_ERR_FILTER_INVAL
;
814 dbg_printf("done\n");
816 dbg_printf("Generating bytecode... ");
818 ret
= filter_visitor_bytecode_generate(ctx
);
820 fprintf(stderr
, "Generate bytecode error\n");
821 ret
= -LTTNG_ERR_FILTER_INVAL
;
824 dbg_printf("done\n");
825 dbg_printf("Size of bytecode generated: %u bytes.\n",
826 bytecode_get_len(&ctx
->bytecode
->b
));
828 lsm
.u
.enable
.bytecode_len
= sizeof(ctx
->bytecode
->b
)
829 + bytecode_get_len(&ctx
->bytecode
->b
);
832 /* Allocate variable length data */
833 if (lsm
.u
.enable
.exclusion_count
!= 0) {
834 varlen_data
= zmalloc(lsm
.u
.enable
.bytecode_len
835 + LTTNG_SYMBOL_NAME_LEN
* exclusion_count
);
837 ret
= -LTTNG_ERR_EXCLUSION_NOMEM
;
838 goto varlen_alloc_error
;
840 /* Put exclusion names first in the data */
841 while (exclusion_count
--) {
842 strncpy(varlen_data
+ LTTNG_SYMBOL_NAME_LEN
* exclusion_count
,
843 *(exclusion_list
+ exclusion_count
),
844 LTTNG_SYMBOL_NAME_LEN
);
846 /* Add filter bytecode next */
847 if (lsm
.u
.enable
.bytecode_len
!= 0) {
848 memcpy(varlen_data
+ LTTNG_SYMBOL_NAME_LEN
* lsm
.u
.enable
.exclusion_count
,
850 lsm
.u
.enable
.bytecode_len
);
853 /* no exclusions - use the already allocated filter bytecode */
854 varlen_data
= (char *)(&ctx
->bytecode
->b
);
857 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, varlen_data
,
858 (LTTNG_SYMBOL_NAME_LEN
* lsm
.u
.enable
.exclusion_count
) +
859 lsm
.u
.enable
.bytecode_len
, NULL
);
861 if (lsm
.u
.enable
.exclusion_count
!= 0) {
866 if (filter_expression
) {
867 filter_bytecode_free(ctx
);
869 filter_parser_ctx_free(ctx
);
870 if (fclose(fmem
) != 0) {
877 filter_bytecode_free(ctx
);
879 filter_parser_ctx_free(ctx
);
881 if (fclose(fmem
) != 0) {
888 * Disable event(s) of a channel and domain.
889 * If no event name is specified, all events are disabled.
890 * If no channel name is specified, the default 'channel0' is used.
891 * Returns size of returned session payload data or a negative error code.
893 int lttng_disable_event(struct lttng_handle
*handle
, const char *name
,
894 const char *channel_name
)
896 struct lttcomm_session_msg lsm
;
898 if (handle
== NULL
) {
899 return -LTTNG_ERR_INVALID
;
902 memset(&lsm
, 0, sizeof(lsm
));
904 /* If no channel name, send empty string. */
905 if (channel_name
== NULL
) {
906 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, "",
907 sizeof(lsm
.u
.disable
.channel_name
));
909 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, channel_name
,
910 sizeof(lsm
.u
.disable
.channel_name
));
913 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
916 lttng_ctl_copy_string(lsm
.u
.disable
.name
, name
,
917 sizeof(lsm
.u
.disable
.name
));
918 lsm
.cmd_type
= LTTNG_DISABLE_EVENT
;
920 lsm
.cmd_type
= LTTNG_DISABLE_ALL_EVENT
;
923 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
924 sizeof(lsm
.session
.name
));
926 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
930 * Enable channel per domain
931 * Returns size of returned session payload data or a negative error code.
933 int lttng_enable_channel(struct lttng_handle
*handle
,
934 struct lttng_channel
*chan
)
936 struct lttcomm_session_msg lsm
;
939 * NULL arguments are forbidden. No default values.
941 if (handle
== NULL
|| chan
== NULL
) {
942 return -LTTNG_ERR_INVALID
;
945 memset(&lsm
, 0, sizeof(lsm
));
947 memcpy(&lsm
.u
.channel
.chan
, chan
, sizeof(lsm
.u
.channel
.chan
));
949 lsm
.cmd_type
= LTTNG_ENABLE_CHANNEL
;
951 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
953 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
954 sizeof(lsm
.session
.name
));
956 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
960 * All tracing will be stopped for registered events of the channel.
961 * Returns size of returned session payload data or a negative error code.
963 int lttng_disable_channel(struct lttng_handle
*handle
, const char *name
)
965 struct lttcomm_session_msg lsm
;
967 /* Safety check. Both are mandatory */
968 if (handle
== NULL
|| name
== NULL
) {
969 return -LTTNG_ERR_INVALID
;
972 memset(&lsm
, 0, sizeof(lsm
));
974 lsm
.cmd_type
= LTTNG_DISABLE_CHANNEL
;
976 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, name
,
977 sizeof(lsm
.u
.disable
.channel_name
));
979 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
981 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
982 sizeof(lsm
.session
.name
));
984 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
988 * Lists all available tracepoints of domain.
989 * Sets the contents of the events array.
990 * Returns the number of lttng_event entries in events;
991 * on error, returns a negative value.
993 int lttng_list_tracepoints(struct lttng_handle
*handle
,
994 struct lttng_event
**events
)
997 struct lttcomm_session_msg lsm
;
999 if (handle
== NULL
) {
1000 return -LTTNG_ERR_INVALID
;
1003 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINTS
;
1004 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1006 ret
= lttng_ctl_ask_sessiond(&lsm
, (void **) events
);
1011 return ret
/ sizeof(struct lttng_event
);
1015 * Lists all available tracepoint fields of domain.
1016 * Sets the contents of the event field array.
1017 * Returns the number of lttng_event_field entries in events;
1018 * on error, returns a negative value.
1020 int lttng_list_tracepoint_fields(struct lttng_handle
*handle
,
1021 struct lttng_event_field
**fields
)
1024 struct lttcomm_session_msg lsm
;
1026 if (handle
== NULL
) {
1027 return -LTTNG_ERR_INVALID
;
1030 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINT_FIELDS
;
1031 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1033 ret
= lttng_ctl_ask_sessiond(&lsm
, (void **) fields
);
1038 return ret
/ sizeof(struct lttng_event_field
);
1042 * Returns a human readable string describing
1043 * the error code (a negative value).
1045 const char *lttng_strerror(int code
)
1047 return error_get_str(code
);
1051 * Create a brand new session using name and url for destination.
1053 * Returns LTTNG_OK on success or a negative error code.
1055 int lttng_create_session(const char *name
, const char *url
)
1059 struct lttcomm_session_msg lsm
;
1060 struct lttng_uri
*uris
= NULL
;
1063 return -LTTNG_ERR_INVALID
;
1066 memset(&lsm
, 0, sizeof(lsm
));
1068 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1069 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1071 /* There should never be a data URL */
1072 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1074 return -LTTNG_ERR_INVALID
;
1077 lsm
.u
.uri
.size
= size
;
1079 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1080 sizeof(struct lttng_uri
) * size
, NULL
);
1087 * Destroy session using name.
1088 * Returns size of returned session payload data or a negative error code.
1090 int lttng_destroy_session(const char *session_name
)
1092 struct lttcomm_session_msg lsm
;
1094 if (session_name
== NULL
) {
1095 return -LTTNG_ERR_INVALID
;
1098 lsm
.cmd_type
= LTTNG_DESTROY_SESSION
;
1100 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1101 sizeof(lsm
.session
.name
));
1103 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1107 * Ask the session daemon for all available sessions.
1108 * Sets the contents of the sessions array.
1109 * Returns the number of lttng_session entries in sessions;
1110 * on error, returns a negative value.
1112 int lttng_list_sessions(struct lttng_session
**sessions
)
1115 struct lttcomm_session_msg lsm
;
1117 lsm
.cmd_type
= LTTNG_LIST_SESSIONS
;
1118 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) sessions
);
1123 return ret
/ sizeof(struct lttng_session
);
1127 * Ask the session daemon for all available domains of a session.
1128 * Sets the contents of the domains array.
1129 * Returns the number of lttng_domain entries in domains;
1130 * on error, returns a negative value.
1132 int lttng_list_domains(const char *session_name
,
1133 struct lttng_domain
**domains
)
1136 struct lttcomm_session_msg lsm
;
1138 if (session_name
== NULL
) {
1139 return -LTTNG_ERR_INVALID
;
1142 lsm
.cmd_type
= LTTNG_LIST_DOMAINS
;
1144 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1145 sizeof(lsm
.session
.name
));
1147 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) domains
);
1152 return ret
/ sizeof(struct lttng_domain
);
1156 * Ask the session daemon for all available channels of a session.
1157 * Sets the contents of the channels array.
1158 * Returns the number of lttng_channel entries in channels;
1159 * on error, returns a negative value.
1161 int lttng_list_channels(struct lttng_handle
*handle
,
1162 struct lttng_channel
**channels
)
1165 struct lttcomm_session_msg lsm
;
1167 if (handle
== NULL
) {
1168 return -LTTNG_ERR_INVALID
;
1171 lsm
.cmd_type
= LTTNG_LIST_CHANNELS
;
1172 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1173 sizeof(lsm
.session
.name
));
1175 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1177 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) channels
);
1182 return ret
/ sizeof(struct lttng_channel
);
1186 * Ask the session daemon for all available events of a session channel.
1187 * Sets the contents of the events array.
1188 * Returns the number of lttng_event entries in events;
1189 * on error, returns a negative value.
1191 int lttng_list_events(struct lttng_handle
*handle
,
1192 const char *channel_name
, struct lttng_event
**events
)
1195 struct lttcomm_session_msg lsm
;
1197 /* Safety check. An handle and channel name are mandatory */
1198 if (handle
== NULL
|| channel_name
== NULL
) {
1199 return -LTTNG_ERR_INVALID
;
1202 lsm
.cmd_type
= LTTNG_LIST_EVENTS
;
1203 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1204 sizeof(lsm
.session
.name
));
1205 lttng_ctl_copy_string(lsm
.u
.list
.channel_name
, channel_name
,
1206 sizeof(lsm
.u
.list
.channel_name
));
1208 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1210 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) events
);
1215 return ret
/ sizeof(struct lttng_event
);
1219 * Sets the tracing_group variable with name.
1220 * This function allocates memory pointed to by tracing_group.
1221 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
1223 int lttng_set_tracing_group(const char *name
)
1226 return -LTTNG_ERR_INVALID
;
1229 if (asprintf(&tracing_group
, "%s", name
) < 0) {
1230 return -LTTNG_ERR_FATAL
;
1237 * Returns size of returned session payload data or a negative error code.
1239 int lttng_calibrate(struct lttng_handle
*handle
,
1240 struct lttng_calibrate
*calibrate
)
1242 struct lttcomm_session_msg lsm
;
1244 /* Safety check. NULL pointer are forbidden */
1245 if (handle
== NULL
|| calibrate
== NULL
) {
1246 return -LTTNG_ERR_INVALID
;
1249 lsm
.cmd_type
= LTTNG_CALIBRATE
;
1250 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1252 memcpy(&lsm
.u
.calibrate
, calibrate
, sizeof(lsm
.u
.calibrate
));
1254 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1258 * Set default channel attributes.
1259 * If either or both of the arguments are null, attr content is zeroe'd.
1261 void lttng_channel_set_default_attr(struct lttng_domain
*domain
,
1262 struct lttng_channel_attr
*attr
)
1265 if (attr
== NULL
|| domain
== NULL
) {
1269 memset(attr
, 0, sizeof(struct lttng_channel_attr
));
1271 /* Same for all domains. */
1272 attr
->overwrite
= DEFAULT_CHANNEL_OVERWRITE
;
1273 attr
->tracefile_size
= DEFAULT_CHANNEL_TRACEFILE_SIZE
;
1274 attr
->tracefile_count
= DEFAULT_CHANNEL_TRACEFILE_COUNT
;
1276 switch (domain
->type
) {
1277 case LTTNG_DOMAIN_KERNEL
:
1278 attr
->switch_timer_interval
= DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER
;
1279 attr
->read_timer_interval
= DEFAULT_KERNEL_CHANNEL_READ_TIMER
;
1280 attr
->subbuf_size
= default_get_kernel_channel_subbuf_size();
1281 attr
->num_subbuf
= DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM
;
1282 attr
->output
= DEFAULT_KERNEL_CHANNEL_OUTPUT
;
1284 case LTTNG_DOMAIN_UST
:
1285 switch (domain
->buf_type
) {
1286 case LTTNG_BUFFER_PER_UID
:
1287 attr
->subbuf_size
= default_get_ust_uid_channel_subbuf_size();
1288 attr
->num_subbuf
= DEFAULT_UST_UID_CHANNEL_SUBBUF_NUM
;
1289 attr
->output
= DEFAULT_UST_UID_CHANNEL_OUTPUT
;
1290 attr
->switch_timer_interval
= DEFAULT_UST_UID_CHANNEL_SWITCH_TIMER
;
1291 attr
->read_timer_interval
= DEFAULT_UST_UID_CHANNEL_READ_TIMER
;
1293 case LTTNG_BUFFER_PER_PID
:
1295 attr
->subbuf_size
= default_get_ust_pid_channel_subbuf_size();
1296 attr
->num_subbuf
= DEFAULT_UST_PID_CHANNEL_SUBBUF_NUM
;
1297 attr
->output
= DEFAULT_UST_PID_CHANNEL_OUTPUT
;
1298 attr
->switch_timer_interval
= DEFAULT_UST_PID_CHANNEL_SWITCH_TIMER
;
1299 attr
->read_timer_interval
= DEFAULT_UST_PID_CHANNEL_READ_TIMER
;
1303 /* Default behavior: leave set to 0. */
1309 * Check if session daemon is alive.
1311 * Return 1 if alive or 0 if not.
1312 * On error returns a negative value.
1314 int lttng_session_daemon_alive(void)
1318 ret
= set_session_daemon_path();
1324 if (*sessiond_sock_path
== '\0') {
1326 * No socket path set. Weird error which means the constructor was not
1332 ret
= try_connect_sessiond(sessiond_sock_path
);
1343 * Set URL for a consumer for a session and domain.
1345 * Return 0 on success, else a negative value.
1347 int lttng_set_consumer_url(struct lttng_handle
*handle
,
1348 const char *control_url
, const char *data_url
)
1352 struct lttcomm_session_msg lsm
;
1353 struct lttng_uri
*uris
= NULL
;
1355 if (handle
== NULL
|| (control_url
== NULL
&& data_url
== NULL
)) {
1356 return -LTTNG_ERR_INVALID
;
1359 memset(&lsm
, 0, sizeof(lsm
));
1361 lsm
.cmd_type
= LTTNG_SET_CONSUMER_URI
;
1363 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1364 sizeof(lsm
.session
.name
));
1365 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1367 size
= uri_parse_str_urls(control_url
, data_url
, &uris
);
1369 return -LTTNG_ERR_INVALID
;
1372 lsm
.u
.uri
.size
= size
;
1374 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1375 sizeof(struct lttng_uri
) * size
, NULL
);
1384 int lttng_enable_consumer(struct lttng_handle
*handle
)
1392 int lttng_disable_consumer(struct lttng_handle
*handle
)
1398 * This is an extension of create session that is ONLY and SHOULD only be used
1399 * by the lttng command line program. It exists to avoid using URI parsing in
1402 * We need the date and time for the trace path subdirectory for the case where
1403 * the user does NOT define one using either -o or -U. Using the normal
1404 * lttng_create_session API call, we have no clue on the session daemon side if
1405 * the URL was generated automatically by the client or define by the user.
1407 * So this function "wrapper" is hidden from the public API, takes the datetime
1408 * string and appends it if necessary to the URI subdirectory before sending it
1409 * to the session daemon.
1411 * With this extra function, the lttng_create_session call behavior is not
1412 * changed and the timestamp is appended to the URI on the session daemon side
1415 int _lttng_create_session_ext(const char *name
, const char *url
,
1416 const char *datetime
)
1420 struct lttcomm_session_msg lsm
;
1421 struct lttng_uri
*uris
= NULL
;
1423 if (name
== NULL
|| datetime
== NULL
) {
1424 return -LTTNG_ERR_INVALID
;
1427 memset(&lsm
, 0, sizeof(lsm
));
1429 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1430 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1432 /* There should never be a data URL */
1433 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1435 ret
= -LTTNG_ERR_INVALID
;
1439 lsm
.u
.uri
.size
= size
;
1441 if (size
> 0 && uris
[0].dtype
!= LTTNG_DST_PATH
&& strlen(uris
[0].subdir
) == 0) {
1442 /* Don't append datetime if the name was automatically created. */
1443 if (strncmp(name
, DEFAULT_SESSION_NAME
"-",
1444 strlen(DEFAULT_SESSION_NAME
) + 1)) {
1445 ret
= snprintf(uris
[0].subdir
, sizeof(uris
[0].subdir
), "%s-%s",
1448 ret
= snprintf(uris
[0].subdir
, sizeof(uris
[0].subdir
), "%s", name
);
1451 PERROR("snprintf uri subdir");
1452 ret
= -LTTNG_ERR_FATAL
;
1457 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1458 sizeof(struct lttng_uri
) * size
, NULL
);
1466 * For a given session name, this call checks if the data is ready to be read
1467 * or is still being extracted by the consumer(s) hence not ready to be used by
1470 int lttng_data_pending(const char *session_name
)
1473 struct lttcomm_session_msg lsm
;
1475 if (session_name
== NULL
) {
1476 return -LTTNG_ERR_INVALID
;
1479 lsm
.cmd_type
= LTTNG_DATA_PENDING
;
1481 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1482 sizeof(lsm
.session
.name
));
1484 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
1487 * The lttng_ctl_ask_sessiond function negate the return code if it's not
1488 * LTTNG_OK so getting -1 means that the reply ret_code was 1 thus meaning
1489 * that the data is available. Yes it is hackish but for now this is the
1500 * Create a session exclusively used for snapshot.
1502 * Returns LTTNG_OK on success or a negative error code.
1504 int lttng_create_session_snapshot(const char *name
, const char *snapshot_url
)
1508 struct lttcomm_session_msg lsm
;
1509 struct lttng_uri
*uris
= NULL
;
1512 return -LTTNG_ERR_INVALID
;
1515 memset(&lsm
, 0, sizeof(lsm
));
1517 lsm
.cmd_type
= LTTNG_CREATE_SESSION_SNAPSHOT
;
1518 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1520 size
= uri_parse_str_urls(snapshot_url
, NULL
, &uris
);
1522 return -LTTNG_ERR_INVALID
;
1525 lsm
.u
.uri
.size
= size
;
1527 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1528 sizeof(struct lttng_uri
) * size
, NULL
);
1535 * Create a session exclusively used for live.
1537 * Returns LTTNG_OK on success or a negative error code.
1539 int lttng_create_session_live(const char *name
, const char *url
,
1540 unsigned int timer_interval
)
1544 struct lttcomm_session_msg lsm
;
1545 struct lttng_uri
*uris
= NULL
;
1548 return -LTTNG_ERR_INVALID
;
1551 memset(&lsm
, 0, sizeof(lsm
));
1553 lsm
.cmd_type
= LTTNG_CREATE_SESSION_LIVE
;
1554 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1556 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1558 ret
= -LTTNG_ERR_INVALID
;
1562 /* file:// is not accepted for live session. */
1563 if (uris
[0].dtype
== LTTNG_DST_PATH
) {
1564 ret
= -LTTNG_ERR_INVALID
;
1568 lsm
.u
.session_live
.nb_uri
= size
;
1569 lsm
.u
.session_live
.timer_interval
= timer_interval
;
1571 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1572 sizeof(struct lttng_uri
) * size
, NULL
);
1582 static void __attribute__((constructor
)) init()
1584 /* Set default session group */
1585 lttng_set_tracing_group(DEFAULT_TRACING_GROUP
);
1591 static void __attribute__((destructor
)) lttng_ctl_exit()
1593 free(tracing_group
);