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
);
738 /* figure out correct command type, based on if we have a filter or exclusions */
739 if (exclusion_count
== 0) {
740 if (filter_expression
== NULL
) {
741 if (ev
->name
[0] != '\0') {
742 lsm
.cmd_type
= LTTNG_ENABLE_EVENT
;
744 lsm
.cmd_type
= LTTNG_ENABLE_ALL_EVENT
;
747 lsm
.cmd_type
= LTTNG_ENABLE_EVENT_WITH_FILTER
;
750 lsm
.cmd_type
= LTTNG_ENABLE_EVENT_WITH_EXCLUSION
;
753 memcpy(&lsm
.u
.enable
.event
, ev
, sizeof(lsm
.u
.enable
.event
));
755 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
756 sizeof(lsm
.session
.name
));
757 lsm
.u
.enable
.exclusion_count
= exclusion_count
;
758 lsm
.u
.enable
.bytecode_len
= 0;
760 if (exclusion_count
== 0 && filter_expression
== NULL
) {
761 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
766 * We have either a filter or some exclusions, so we need to set up
767 * a variable-length memory block from where to send the data
770 /* Parse filter expression */
771 if (filter_expression
!= NULL
) {
774 * casting const to non-const, as the underlying function will
775 * use it in read-only mode.
777 fmem
= lttng_fmemopen((void *) filter_expression
,
778 strlen(filter_expression
), "r");
780 fprintf(stderr
, "Error opening memory as stream\n");
781 return -LTTNG_ERR_FILTER_NOMEM
;
783 ctx
= filter_parser_ctx_alloc(fmem
);
785 fprintf(stderr
, "Error allocating parser\n");
786 ret
= -LTTNG_ERR_FILTER_NOMEM
;
787 goto filter_alloc_error
;
789 ret
= filter_parser_ctx_append_ast(ctx
);
791 fprintf(stderr
, "Parse error\n");
792 ret
= -LTTNG_ERR_FILTER_INVAL
;
795 ret
= filter_visitor_set_parent(ctx
);
797 fprintf(stderr
, "Set parent error\n");
798 ret
= -LTTNG_ERR_FILTER_INVAL
;
802 ret
= filter_visitor_print_xml(ctx
, stdout
, 0);
805 fprintf(stderr
, "XML print error\n");
806 ret
= -LTTNG_ERR_FILTER_INVAL
;
811 dbg_printf("Generating IR... ");
813 ret
= filter_visitor_ir_generate(ctx
);
815 fprintf(stderr
, "Generate IR error\n");
816 ret
= -LTTNG_ERR_FILTER_INVAL
;
819 dbg_printf("done\n");
821 dbg_printf("Validating IR... ");
823 ret
= filter_visitor_ir_check_binary_op_nesting(ctx
);
825 ret
= -LTTNG_ERR_FILTER_INVAL
;
828 dbg_printf("done\n");
830 dbg_printf("Generating bytecode... ");
832 ret
= filter_visitor_bytecode_generate(ctx
);
834 fprintf(stderr
, "Generate bytecode error\n");
835 ret
= -LTTNG_ERR_FILTER_INVAL
;
838 dbg_printf("done\n");
839 dbg_printf("Size of bytecode generated: %u bytes.\n",
840 bytecode_get_len(&ctx
->bytecode
->b
));
842 lsm
.u
.enable
.bytecode_len
= sizeof(ctx
->bytecode
->b
)
843 + bytecode_get_len(&ctx
->bytecode
->b
);
846 /* Allocate variable length data */
847 if (lsm
.u
.enable
.exclusion_count
!= 0) {
848 varlen_data
= zmalloc(lsm
.u
.enable
.bytecode_len
849 + LTTNG_SYMBOL_NAME_LEN
* exclusion_count
);
851 ret
= -LTTNG_ERR_EXCLUSION_NOMEM
;
852 goto varlen_alloc_error
;
854 /* Put exclusion names first in the data */
855 while (exclusion_count
--) {
856 strncpy(varlen_data
+ LTTNG_SYMBOL_NAME_LEN
* exclusion_count
,
857 *(exclusion_list
+ exclusion_count
),
858 LTTNG_SYMBOL_NAME_LEN
);
860 /* Add filter bytecode next */
861 if (lsm
.u
.enable
.bytecode_len
!= 0) {
862 memcpy(varlen_data
+ LTTNG_SYMBOL_NAME_LEN
* lsm
.u
.enable
.exclusion_count
,
864 lsm
.u
.enable
.bytecode_len
);
867 /* no exclusions - use the already allocated filter bytecode */
868 varlen_data
= (char *)(&ctx
->bytecode
->b
);
871 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, varlen_data
,
872 LTTNG_SYMBOL_NAME_LEN
* lsm
.u
.enable
.exclusion_count
873 + lsm
.u
.enable
.bytecode_len
,
876 if (lsm
.u
.enable
.exclusion_count
!= 0) {
881 if (filter_expression
) {
882 filter_bytecode_free(ctx
);
884 filter_parser_ctx_free(ctx
);
885 if (fclose(fmem
) != 0) {
892 filter_bytecode_free(ctx
);
894 filter_parser_ctx_free(ctx
);
896 if (fclose(fmem
) != 0) {
903 * Disable event(s) of a channel and domain.
904 * If no event name is specified, all events are disabled.
905 * If no channel name is specified, the default 'channel0' is used.
906 * Returns size of returned session payload data or a negative error code.
908 int lttng_disable_event(struct lttng_handle
*handle
, const char *name
,
909 const char *channel_name
)
911 struct lttcomm_session_msg lsm
;
913 if (handle
== NULL
) {
914 return -LTTNG_ERR_INVALID
;
917 memset(&lsm
, 0, sizeof(lsm
));
919 /* If no channel name, send empty string. */
920 if (channel_name
== NULL
) {
921 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, "",
922 sizeof(lsm
.u
.disable
.channel_name
));
924 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, channel_name
,
925 sizeof(lsm
.u
.disable
.channel_name
));
928 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
931 lttng_ctl_copy_string(lsm
.u
.disable
.name
, name
,
932 sizeof(lsm
.u
.disable
.name
));
933 lsm
.cmd_type
= LTTNG_DISABLE_EVENT
;
935 lsm
.cmd_type
= LTTNG_DISABLE_ALL_EVENT
;
938 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
939 sizeof(lsm
.session
.name
));
941 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
945 * Enable channel per domain
946 * Returns size of returned session payload data or a negative error code.
948 int lttng_enable_channel(struct lttng_handle
*handle
,
949 struct lttng_channel
*chan
)
951 struct lttcomm_session_msg lsm
;
954 * NULL arguments are forbidden. No default values.
956 if (handle
== NULL
|| chan
== NULL
) {
957 return -LTTNG_ERR_INVALID
;
960 memset(&lsm
, 0, sizeof(lsm
));
962 memcpy(&lsm
.u
.channel
.chan
, chan
, sizeof(lsm
.u
.channel
.chan
));
964 lsm
.cmd_type
= LTTNG_ENABLE_CHANNEL
;
966 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
968 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
969 sizeof(lsm
.session
.name
));
971 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
975 * All tracing will be stopped for registered events of the channel.
976 * Returns size of returned session payload data or a negative error code.
978 int lttng_disable_channel(struct lttng_handle
*handle
, const char *name
)
980 struct lttcomm_session_msg lsm
;
982 /* Safety check. Both are mandatory */
983 if (handle
== NULL
|| name
== NULL
) {
984 return -LTTNG_ERR_INVALID
;
987 memset(&lsm
, 0, sizeof(lsm
));
989 lsm
.cmd_type
= LTTNG_DISABLE_CHANNEL
;
991 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, name
,
992 sizeof(lsm
.u
.disable
.channel_name
));
994 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
996 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
997 sizeof(lsm
.session
.name
));
999 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1003 * Lists all available tracepoints of domain.
1004 * Sets the contents of the events array.
1005 * Returns the number of lttng_event entries in events;
1006 * on error, returns a negative value.
1008 int lttng_list_tracepoints(struct lttng_handle
*handle
,
1009 struct lttng_event
**events
)
1012 struct lttcomm_session_msg lsm
;
1014 if (handle
== NULL
) {
1015 return -LTTNG_ERR_INVALID
;
1018 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINTS
;
1019 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1021 ret
= lttng_ctl_ask_sessiond(&lsm
, (void **) events
);
1026 return ret
/ sizeof(struct lttng_event
);
1030 * Lists all available tracepoint fields of domain.
1031 * Sets the contents of the event field array.
1032 * Returns the number of lttng_event_field entries in events;
1033 * on error, returns a negative value.
1035 int lttng_list_tracepoint_fields(struct lttng_handle
*handle
,
1036 struct lttng_event_field
**fields
)
1039 struct lttcomm_session_msg lsm
;
1041 if (handle
== NULL
) {
1042 return -LTTNG_ERR_INVALID
;
1045 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINT_FIELDS
;
1046 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1048 ret
= lttng_ctl_ask_sessiond(&lsm
, (void **) fields
);
1053 return ret
/ sizeof(struct lttng_event_field
);
1057 * Returns a human readable string describing
1058 * the error code (a negative value).
1060 const char *lttng_strerror(int code
)
1062 return error_get_str(code
);
1066 * Create a brand new session using name and url for destination.
1068 * Returns LTTNG_OK on success or a negative error code.
1070 int lttng_create_session(const char *name
, const char *url
)
1074 struct lttcomm_session_msg lsm
;
1075 struct lttng_uri
*uris
= NULL
;
1078 return -LTTNG_ERR_INVALID
;
1081 memset(&lsm
, 0, sizeof(lsm
));
1083 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1084 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1086 /* There should never be a data URL */
1087 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1089 return -LTTNG_ERR_INVALID
;
1092 lsm
.u
.uri
.size
= size
;
1094 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1095 sizeof(struct lttng_uri
) * size
, NULL
);
1102 * Destroy session using name.
1103 * Returns size of returned session payload data or a negative error code.
1105 int lttng_destroy_session(const char *session_name
)
1107 struct lttcomm_session_msg lsm
;
1109 if (session_name
== NULL
) {
1110 return -LTTNG_ERR_INVALID
;
1113 lsm
.cmd_type
= LTTNG_DESTROY_SESSION
;
1115 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1116 sizeof(lsm
.session
.name
));
1118 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1122 * Ask the session daemon for all available sessions.
1123 * Sets the contents of the sessions array.
1124 * Returns the number of lttng_session entries in sessions;
1125 * on error, returns a negative value.
1127 int lttng_list_sessions(struct lttng_session
**sessions
)
1130 struct lttcomm_session_msg lsm
;
1132 lsm
.cmd_type
= LTTNG_LIST_SESSIONS
;
1133 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) sessions
);
1138 return ret
/ sizeof(struct lttng_session
);
1142 * Ask the session daemon for all available domains of a session.
1143 * Sets the contents of the domains array.
1144 * Returns the number of lttng_domain entries in domains;
1145 * on error, returns a negative value.
1147 int lttng_list_domains(const char *session_name
,
1148 struct lttng_domain
**domains
)
1151 struct lttcomm_session_msg lsm
;
1153 if (session_name
== NULL
) {
1154 return -LTTNG_ERR_INVALID
;
1157 lsm
.cmd_type
= LTTNG_LIST_DOMAINS
;
1159 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1160 sizeof(lsm
.session
.name
));
1162 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) domains
);
1167 return ret
/ sizeof(struct lttng_domain
);
1171 * Ask the session daemon for all available channels of a session.
1172 * Sets the contents of the channels array.
1173 * Returns the number of lttng_channel entries in channels;
1174 * on error, returns a negative value.
1176 int lttng_list_channels(struct lttng_handle
*handle
,
1177 struct lttng_channel
**channels
)
1180 struct lttcomm_session_msg lsm
;
1182 if (handle
== NULL
) {
1183 return -LTTNG_ERR_INVALID
;
1186 lsm
.cmd_type
= LTTNG_LIST_CHANNELS
;
1187 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1188 sizeof(lsm
.session
.name
));
1190 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1192 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) channels
);
1197 return ret
/ sizeof(struct lttng_channel
);
1201 * Ask the session daemon for all available events of a session channel.
1202 * Sets the contents of the events array.
1203 * Returns the number of lttng_event entries in events;
1204 * on error, returns a negative value.
1206 int lttng_list_events(struct lttng_handle
*handle
,
1207 const char *channel_name
, struct lttng_event
**events
)
1210 struct lttcomm_session_msg lsm
;
1212 /* Safety check. An handle and channel name are mandatory */
1213 if (handle
== NULL
|| channel_name
== NULL
) {
1214 return -LTTNG_ERR_INVALID
;
1217 lsm
.cmd_type
= LTTNG_LIST_EVENTS
;
1218 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1219 sizeof(lsm
.session
.name
));
1220 lttng_ctl_copy_string(lsm
.u
.list
.channel_name
, channel_name
,
1221 sizeof(lsm
.u
.list
.channel_name
));
1223 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1225 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) events
);
1230 return ret
/ sizeof(struct lttng_event
);
1234 * Sets the tracing_group variable with name.
1235 * This function allocates memory pointed to by tracing_group.
1236 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
1238 int lttng_set_tracing_group(const char *name
)
1241 return -LTTNG_ERR_INVALID
;
1244 if (asprintf(&tracing_group
, "%s", name
) < 0) {
1245 return -LTTNG_ERR_FATAL
;
1252 * Returns size of returned session payload data or a negative error code.
1254 int lttng_calibrate(struct lttng_handle
*handle
,
1255 struct lttng_calibrate
*calibrate
)
1257 struct lttcomm_session_msg lsm
;
1259 /* Safety check. NULL pointer are forbidden */
1260 if (handle
== NULL
|| calibrate
== NULL
) {
1261 return -LTTNG_ERR_INVALID
;
1264 lsm
.cmd_type
= LTTNG_CALIBRATE
;
1265 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1267 memcpy(&lsm
.u
.calibrate
, calibrate
, sizeof(lsm
.u
.calibrate
));
1269 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1273 * Set default channel attributes.
1274 * If either or both of the arguments are null, attr content is zeroe'd.
1276 void lttng_channel_set_default_attr(struct lttng_domain
*domain
,
1277 struct lttng_channel_attr
*attr
)
1280 if (attr
== NULL
|| domain
== NULL
) {
1284 memset(attr
, 0, sizeof(struct lttng_channel_attr
));
1286 /* Same for all domains. */
1287 attr
->overwrite
= DEFAULT_CHANNEL_OVERWRITE
;
1288 attr
->tracefile_size
= DEFAULT_CHANNEL_TRACEFILE_SIZE
;
1289 attr
->tracefile_count
= DEFAULT_CHANNEL_TRACEFILE_COUNT
;
1291 switch (domain
->type
) {
1292 case LTTNG_DOMAIN_KERNEL
:
1293 attr
->switch_timer_interval
= DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER
;
1294 attr
->read_timer_interval
= DEFAULT_KERNEL_CHANNEL_READ_TIMER
;
1295 attr
->subbuf_size
= default_get_kernel_channel_subbuf_size();
1296 attr
->num_subbuf
= DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM
;
1297 attr
->output
= DEFAULT_KERNEL_CHANNEL_OUTPUT
;
1299 case LTTNG_DOMAIN_UST
:
1300 switch (domain
->buf_type
) {
1301 case LTTNG_BUFFER_PER_UID
:
1302 attr
->subbuf_size
= default_get_ust_uid_channel_subbuf_size();
1303 attr
->num_subbuf
= DEFAULT_UST_UID_CHANNEL_SUBBUF_NUM
;
1304 attr
->output
= DEFAULT_UST_UID_CHANNEL_OUTPUT
;
1305 attr
->switch_timer_interval
= DEFAULT_UST_UID_CHANNEL_SWITCH_TIMER
;
1306 attr
->read_timer_interval
= DEFAULT_UST_UID_CHANNEL_READ_TIMER
;
1308 case LTTNG_BUFFER_PER_PID
:
1310 attr
->subbuf_size
= default_get_ust_pid_channel_subbuf_size();
1311 attr
->num_subbuf
= DEFAULT_UST_PID_CHANNEL_SUBBUF_NUM
;
1312 attr
->output
= DEFAULT_UST_PID_CHANNEL_OUTPUT
;
1313 attr
->switch_timer_interval
= DEFAULT_UST_PID_CHANNEL_SWITCH_TIMER
;
1314 attr
->read_timer_interval
= DEFAULT_UST_PID_CHANNEL_READ_TIMER
;
1318 /* Default behavior: leave set to 0. */
1324 * Check if session daemon is alive.
1326 * Return 1 if alive or 0 if not.
1327 * On error returns a negative value.
1329 int lttng_session_daemon_alive(void)
1333 ret
= set_session_daemon_path();
1339 if (*sessiond_sock_path
== '\0') {
1341 * No socket path set. Weird error which means the constructor was not
1347 ret
= try_connect_sessiond(sessiond_sock_path
);
1358 * Set URL for a consumer for a session and domain.
1360 * Return 0 on success, else a negative value.
1362 int lttng_set_consumer_url(struct lttng_handle
*handle
,
1363 const char *control_url
, const char *data_url
)
1367 struct lttcomm_session_msg lsm
;
1368 struct lttng_uri
*uris
= NULL
;
1370 if (handle
== NULL
|| (control_url
== NULL
&& data_url
== NULL
)) {
1371 return -LTTNG_ERR_INVALID
;
1374 memset(&lsm
, 0, sizeof(lsm
));
1376 lsm
.cmd_type
= LTTNG_SET_CONSUMER_URI
;
1378 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1379 sizeof(lsm
.session
.name
));
1380 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1382 size
= uri_parse_str_urls(control_url
, data_url
, &uris
);
1384 return -LTTNG_ERR_INVALID
;
1387 lsm
.u
.uri
.size
= size
;
1389 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1390 sizeof(struct lttng_uri
) * size
, NULL
);
1399 int lttng_enable_consumer(struct lttng_handle
*handle
)
1407 int lttng_disable_consumer(struct lttng_handle
*handle
)
1413 * This is an extension of create session that is ONLY and SHOULD only be used
1414 * by the lttng command line program. It exists to avoid using URI parsing in
1417 * We need the date and time for the trace path subdirectory for the case where
1418 * the user does NOT define one using either -o or -U. Using the normal
1419 * lttng_create_session API call, we have no clue on the session daemon side if
1420 * the URL was generated automatically by the client or define by the user.
1422 * So this function "wrapper" is hidden from the public API, takes the datetime
1423 * string and appends it if necessary to the URI subdirectory before sending it
1424 * to the session daemon.
1426 * With this extra function, the lttng_create_session call behavior is not
1427 * changed and the timestamp is appended to the URI on the session daemon side
1430 int _lttng_create_session_ext(const char *name
, const char *url
,
1431 const char *datetime
)
1435 struct lttcomm_session_msg lsm
;
1436 struct lttng_uri
*uris
= NULL
;
1438 if (name
== NULL
|| datetime
== NULL
) {
1439 return -LTTNG_ERR_INVALID
;
1442 memset(&lsm
, 0, sizeof(lsm
));
1444 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1445 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1447 /* There should never be a data URL */
1448 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1450 ret
= -LTTNG_ERR_INVALID
;
1454 lsm
.u
.uri
.size
= size
;
1456 if (size
> 0 && uris
[0].dtype
!= LTTNG_DST_PATH
&& strlen(uris
[0].subdir
) == 0) {
1457 /* Don't append datetime if the name was automatically created. */
1458 if (strncmp(name
, DEFAULT_SESSION_NAME
"-",
1459 strlen(DEFAULT_SESSION_NAME
) + 1)) {
1460 ret
= snprintf(uris
[0].subdir
, sizeof(uris
[0].subdir
), "%s-%s",
1463 ret
= snprintf(uris
[0].subdir
, sizeof(uris
[0].subdir
), "%s", name
);
1466 PERROR("snprintf uri subdir");
1467 ret
= -LTTNG_ERR_FATAL
;
1472 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1473 sizeof(struct lttng_uri
) * size
, NULL
);
1481 * For a given session name, this call checks if the data is ready to be read
1482 * or is still being extracted by the consumer(s) hence not ready to be used by
1485 int lttng_data_pending(const char *session_name
)
1488 struct lttcomm_session_msg lsm
;
1490 if (session_name
== NULL
) {
1491 return -LTTNG_ERR_INVALID
;
1494 lsm
.cmd_type
= LTTNG_DATA_PENDING
;
1496 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1497 sizeof(lsm
.session
.name
));
1499 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
1502 * The lttng_ctl_ask_sessiond function negate the return code if it's not
1503 * LTTNG_OK so getting -1 means that the reply ret_code was 1 thus meaning
1504 * that the data is available. Yes it is hackish but for now this is the
1515 * Create a session exclusively used for snapshot.
1517 * Returns LTTNG_OK on success or a negative error code.
1519 int lttng_create_session_snapshot(const char *name
, const char *snapshot_url
)
1523 struct lttcomm_session_msg lsm
;
1524 struct lttng_uri
*uris
= NULL
;
1527 return -LTTNG_ERR_INVALID
;
1530 memset(&lsm
, 0, sizeof(lsm
));
1532 lsm
.cmd_type
= LTTNG_CREATE_SESSION_SNAPSHOT
;
1533 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1535 size
= uri_parse_str_urls(snapshot_url
, NULL
, &uris
);
1537 return -LTTNG_ERR_INVALID
;
1540 lsm
.u
.uri
.size
= size
;
1542 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1543 sizeof(struct lttng_uri
) * size
, NULL
);
1550 * Create a session exclusively used for live.
1552 * Returns LTTNG_OK on success or a negative error code.
1554 int lttng_create_session_live(const char *name
, const char *url
,
1555 unsigned int timer_interval
)
1559 struct lttcomm_session_msg lsm
;
1560 struct lttng_uri
*uris
= NULL
;
1563 return -LTTNG_ERR_INVALID
;
1566 memset(&lsm
, 0, sizeof(lsm
));
1568 lsm
.cmd_type
= LTTNG_CREATE_SESSION_LIVE
;
1569 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1571 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1573 ret
= -LTTNG_ERR_INVALID
;
1577 /* file:// is not accepted for live session. */
1578 if (uris
[0].dtype
== LTTNG_DST_PATH
) {
1579 ret
= -LTTNG_ERR_INVALID
;
1583 lsm
.u
.session_live
.nb_uri
= size
;
1584 lsm
.u
.session_live
.timer_interval
= timer_interval
;
1586 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1587 sizeof(struct lttng_uri
) * size
, NULL
);
1597 static void __attribute__((constructor
)) init()
1599 /* Set default session group */
1600 lttng_set_tracing_group(DEFAULT_TRACING_GROUP
);
1606 static void __attribute__((destructor
)) lttng_ctl_exit()
1608 free(tracing_group
);