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 if (ev
->name
[0] != '\0') {
737 lsm
.cmd_type
= LTTNG_ENABLE_EVENT
;
739 lsm
.cmd_type
= LTTNG_ENABLE_ALL_EVENT
;
742 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
743 memcpy(&lsm
.u
.enable
.event
, ev
, sizeof(lsm
.u
.enable
.event
));
745 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
746 sizeof(lsm
.session
.name
));
747 lsm
.u
.enable
.exclusion_count
= exclusion_count
;
748 lsm
.u
.enable
.bytecode_len
= 0;
750 if (exclusion_count
== 0 && filter_expression
== NULL
) {
751 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
756 * We have either a filter or some exclusions, so we need to set up
757 * a variable-length memory block from where to send the data
760 /* Parse filter expression */
761 if (filter_expression
!= NULL
) {
764 * casting const to non-const, as the underlying function will
765 * use it in read-only mode.
767 fmem
= lttng_fmemopen((void *) filter_expression
,
768 strlen(filter_expression
), "r");
770 fprintf(stderr
, "Error opening memory as stream\n");
771 return -LTTNG_ERR_FILTER_NOMEM
;
773 ctx
= filter_parser_ctx_alloc(fmem
);
775 fprintf(stderr
, "Error allocating parser\n");
776 ret
= -LTTNG_ERR_FILTER_NOMEM
;
777 goto filter_alloc_error
;
779 ret
= filter_parser_ctx_append_ast(ctx
);
781 fprintf(stderr
, "Parse error\n");
782 ret
= -LTTNG_ERR_FILTER_INVAL
;
785 ret
= filter_visitor_set_parent(ctx
);
787 fprintf(stderr
, "Set parent error\n");
788 ret
= -LTTNG_ERR_FILTER_INVAL
;
792 ret
= filter_visitor_print_xml(ctx
, stdout
, 0);
795 fprintf(stderr
, "XML print error\n");
796 ret
= -LTTNG_ERR_FILTER_INVAL
;
801 dbg_printf("Generating IR... ");
803 ret
= filter_visitor_ir_generate(ctx
);
805 fprintf(stderr
, "Generate IR error\n");
806 ret
= -LTTNG_ERR_FILTER_INVAL
;
809 dbg_printf("done\n");
811 dbg_printf("Validating IR... ");
813 ret
= filter_visitor_ir_check_binary_op_nesting(ctx
);
815 ret
= -LTTNG_ERR_FILTER_INVAL
;
818 dbg_printf("done\n");
820 dbg_printf("Generating bytecode... ");
822 ret
= filter_visitor_bytecode_generate(ctx
);
824 fprintf(stderr
, "Generate bytecode error\n");
825 ret
= -LTTNG_ERR_FILTER_INVAL
;
828 dbg_printf("done\n");
829 dbg_printf("Size of bytecode generated: %u bytes.\n",
830 bytecode_get_len(&ctx
->bytecode
->b
));
832 lsm
.u
.enable
.bytecode_len
= sizeof(ctx
->bytecode
->b
)
833 + bytecode_get_len(&ctx
->bytecode
->b
);
836 /* Allocate variable length data */
837 if (lsm
.u
.enable
.exclusion_count
!= 0) {
838 varlen_data
= zmalloc(lsm
.u
.enable
.bytecode_len
839 + LTTNG_SYMBOL_NAME_LEN
* exclusion_count
);
841 ret
= -LTTNG_ERR_EXCLUSION_NOMEM
;
842 goto varlen_alloc_error
;
844 /* Put exclusion names first in the data */
845 while (exclusion_count
--) {
846 strncpy(varlen_data
+ LTTNG_SYMBOL_NAME_LEN
* exclusion_count
,
847 *(exclusion_list
+ exclusion_count
),
848 LTTNG_SYMBOL_NAME_LEN
);
850 /* Add filter bytecode next */
851 if (lsm
.u
.enable
.bytecode_len
!= 0) {
852 memcpy(varlen_data
+ LTTNG_SYMBOL_NAME_LEN
* lsm
.u
.enable
.exclusion_count
,
854 lsm
.u
.enable
.bytecode_len
);
857 /* no exclusions - use the already allocated filter bytecode */
858 varlen_data
= (char *)(&ctx
->bytecode
->b
);
861 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, varlen_data
,
862 (LTTNG_SYMBOL_NAME_LEN
* lsm
.u
.enable
.exclusion_count
) +
863 lsm
.u
.enable
.bytecode_len
, NULL
);
865 if (lsm
.u
.enable
.exclusion_count
!= 0) {
870 if (filter_expression
) {
871 filter_bytecode_free(ctx
);
873 filter_parser_ctx_free(ctx
);
874 if (fclose(fmem
) != 0) {
881 filter_bytecode_free(ctx
);
883 filter_parser_ctx_free(ctx
);
885 if (fclose(fmem
) != 0) {
892 * Disable event(s) of a channel and domain.
893 * If no event name is specified, all events are disabled.
894 * If no channel name is specified, the default 'channel0' is used.
895 * Returns size of returned session payload data or a negative error code.
897 int lttng_disable_event(struct lttng_handle
*handle
, const char *name
,
898 const char *channel_name
)
900 struct lttcomm_session_msg lsm
;
902 if (handle
== NULL
) {
903 return -LTTNG_ERR_INVALID
;
906 memset(&lsm
, 0, sizeof(lsm
));
908 /* If no channel name, send empty string. */
909 if (channel_name
== NULL
) {
910 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, "",
911 sizeof(lsm
.u
.disable
.channel_name
));
913 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, channel_name
,
914 sizeof(lsm
.u
.disable
.channel_name
));
917 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
920 lttng_ctl_copy_string(lsm
.u
.disable
.name
, name
,
921 sizeof(lsm
.u
.disable
.name
));
922 lsm
.cmd_type
= LTTNG_DISABLE_EVENT
;
924 lsm
.cmd_type
= LTTNG_DISABLE_ALL_EVENT
;
927 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
928 sizeof(lsm
.session
.name
));
930 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
934 * Enable channel per domain
935 * Returns size of returned session payload data or a negative error code.
937 int lttng_enable_channel(struct lttng_handle
*handle
,
938 struct lttng_channel
*chan
)
940 struct lttcomm_session_msg lsm
;
943 * NULL arguments are forbidden. No default values.
945 if (handle
== NULL
|| chan
== NULL
) {
946 return -LTTNG_ERR_INVALID
;
949 memset(&lsm
, 0, sizeof(lsm
));
951 memcpy(&lsm
.u
.channel
.chan
, chan
, sizeof(lsm
.u
.channel
.chan
));
953 lsm
.cmd_type
= LTTNG_ENABLE_CHANNEL
;
955 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
957 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
958 sizeof(lsm
.session
.name
));
960 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
964 * All tracing will be stopped for registered events of the channel.
965 * Returns size of returned session payload data or a negative error code.
967 int lttng_disable_channel(struct lttng_handle
*handle
, const char *name
)
969 struct lttcomm_session_msg lsm
;
971 /* Safety check. Both are mandatory */
972 if (handle
== NULL
|| name
== NULL
) {
973 return -LTTNG_ERR_INVALID
;
976 memset(&lsm
, 0, sizeof(lsm
));
978 lsm
.cmd_type
= LTTNG_DISABLE_CHANNEL
;
980 lttng_ctl_copy_string(lsm
.u
.disable
.channel_name
, name
,
981 sizeof(lsm
.u
.disable
.channel_name
));
983 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
985 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
986 sizeof(lsm
.session
.name
));
988 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
992 * Lists all available tracepoints of domain.
993 * Sets the contents of the events array.
994 * Returns the number of lttng_event entries in events;
995 * on error, returns a negative value.
997 int lttng_list_tracepoints(struct lttng_handle
*handle
,
998 struct lttng_event
**events
)
1001 struct lttcomm_session_msg lsm
;
1003 if (handle
== NULL
) {
1004 return -LTTNG_ERR_INVALID
;
1007 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINTS
;
1008 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1010 ret
= lttng_ctl_ask_sessiond(&lsm
, (void **) events
);
1015 return ret
/ sizeof(struct lttng_event
);
1019 * Lists all available tracepoint fields of domain.
1020 * Sets the contents of the event field array.
1021 * Returns the number of lttng_event_field entries in events;
1022 * on error, returns a negative value.
1024 int lttng_list_tracepoint_fields(struct lttng_handle
*handle
,
1025 struct lttng_event_field
**fields
)
1028 struct lttcomm_session_msg lsm
;
1030 if (handle
== NULL
) {
1031 return -LTTNG_ERR_INVALID
;
1034 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINT_FIELDS
;
1035 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1037 ret
= lttng_ctl_ask_sessiond(&lsm
, (void **) fields
);
1042 return ret
/ sizeof(struct lttng_event_field
);
1046 * Returns a human readable string describing
1047 * the error code (a negative value).
1049 const char *lttng_strerror(int code
)
1051 return error_get_str(code
);
1055 * Create a brand new session using name and url for destination.
1057 * Returns LTTNG_OK on success or a negative error code.
1059 int lttng_create_session(const char *name
, const char *url
)
1063 struct lttcomm_session_msg lsm
;
1064 struct lttng_uri
*uris
= NULL
;
1067 return -LTTNG_ERR_INVALID
;
1070 memset(&lsm
, 0, sizeof(lsm
));
1072 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1073 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1075 /* There should never be a data URL */
1076 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1078 return -LTTNG_ERR_INVALID
;
1081 lsm
.u
.uri
.size
= size
;
1083 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1084 sizeof(struct lttng_uri
) * size
, NULL
);
1091 * Destroy session using name.
1092 * Returns size of returned session payload data or a negative error code.
1094 int lttng_destroy_session(const char *session_name
)
1096 struct lttcomm_session_msg lsm
;
1098 if (session_name
== NULL
) {
1099 return -LTTNG_ERR_INVALID
;
1102 lsm
.cmd_type
= LTTNG_DESTROY_SESSION
;
1104 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1105 sizeof(lsm
.session
.name
));
1107 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1111 * Ask the session daemon for all available sessions.
1112 * Sets the contents of the sessions array.
1113 * Returns the number of lttng_session entries in sessions;
1114 * on error, returns a negative value.
1116 int lttng_list_sessions(struct lttng_session
**sessions
)
1119 struct lttcomm_session_msg lsm
;
1121 lsm
.cmd_type
= LTTNG_LIST_SESSIONS
;
1122 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) sessions
);
1127 return ret
/ sizeof(struct lttng_session
);
1131 * Ask the session daemon for all available domains of a session.
1132 * Sets the contents of the domains array.
1133 * Returns the number of lttng_domain entries in domains;
1134 * on error, returns a negative value.
1136 int lttng_list_domains(const char *session_name
,
1137 struct lttng_domain
**domains
)
1140 struct lttcomm_session_msg lsm
;
1142 if (session_name
== NULL
) {
1143 return -LTTNG_ERR_INVALID
;
1146 lsm
.cmd_type
= LTTNG_LIST_DOMAINS
;
1148 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1149 sizeof(lsm
.session
.name
));
1151 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) domains
);
1156 return ret
/ sizeof(struct lttng_domain
);
1160 * Ask the session daemon for all available channels of a session.
1161 * Sets the contents of the channels array.
1162 * Returns the number of lttng_channel entries in channels;
1163 * on error, returns a negative value.
1165 int lttng_list_channels(struct lttng_handle
*handle
,
1166 struct lttng_channel
**channels
)
1169 struct lttcomm_session_msg lsm
;
1171 if (handle
== NULL
) {
1172 return -LTTNG_ERR_INVALID
;
1175 lsm
.cmd_type
= LTTNG_LIST_CHANNELS
;
1176 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1177 sizeof(lsm
.session
.name
));
1179 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1181 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) channels
);
1186 return ret
/ sizeof(struct lttng_channel
);
1190 * Ask the session daemon for all available events of a session channel.
1191 * Sets the contents of the events array.
1192 * Returns the number of lttng_event entries in events;
1193 * on error, returns a negative value.
1195 int lttng_list_events(struct lttng_handle
*handle
,
1196 const char *channel_name
, struct lttng_event
**events
)
1199 struct lttcomm_session_msg lsm
;
1201 /* Safety check. An handle and channel name are mandatory */
1202 if (handle
== NULL
|| channel_name
== NULL
) {
1203 return -LTTNG_ERR_INVALID
;
1206 lsm
.cmd_type
= LTTNG_LIST_EVENTS
;
1207 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1208 sizeof(lsm
.session
.name
));
1209 lttng_ctl_copy_string(lsm
.u
.list
.channel_name
, channel_name
,
1210 sizeof(lsm
.u
.list
.channel_name
));
1212 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1214 ret
= lttng_ctl_ask_sessiond(&lsm
, (void**) events
);
1219 return ret
/ sizeof(struct lttng_event
);
1223 * Sets the tracing_group variable with name.
1224 * This function allocates memory pointed to by tracing_group.
1225 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
1227 int lttng_set_tracing_group(const char *name
)
1230 return -LTTNG_ERR_INVALID
;
1233 if (asprintf(&tracing_group
, "%s", name
) < 0) {
1234 return -LTTNG_ERR_FATAL
;
1241 * Returns size of returned session payload data or a negative error code.
1243 int lttng_calibrate(struct lttng_handle
*handle
,
1244 struct lttng_calibrate
*calibrate
)
1246 struct lttcomm_session_msg lsm
;
1248 /* Safety check. NULL pointer are forbidden */
1249 if (handle
== NULL
|| calibrate
== NULL
) {
1250 return -LTTNG_ERR_INVALID
;
1253 lsm
.cmd_type
= LTTNG_CALIBRATE
;
1254 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1256 memcpy(&lsm
.u
.calibrate
, calibrate
, sizeof(lsm
.u
.calibrate
));
1258 return lttng_ctl_ask_sessiond(&lsm
, NULL
);
1262 * Set default channel attributes.
1263 * If either or both of the arguments are null, attr content is zeroe'd.
1265 void lttng_channel_set_default_attr(struct lttng_domain
*domain
,
1266 struct lttng_channel_attr
*attr
)
1269 if (attr
== NULL
|| domain
== NULL
) {
1273 memset(attr
, 0, sizeof(struct lttng_channel_attr
));
1275 /* Same for all domains. */
1276 attr
->overwrite
= DEFAULT_CHANNEL_OVERWRITE
;
1277 attr
->tracefile_size
= DEFAULT_CHANNEL_TRACEFILE_SIZE
;
1278 attr
->tracefile_count
= DEFAULT_CHANNEL_TRACEFILE_COUNT
;
1280 switch (domain
->type
) {
1281 case LTTNG_DOMAIN_KERNEL
:
1282 attr
->switch_timer_interval
= DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER
;
1283 attr
->read_timer_interval
= DEFAULT_KERNEL_CHANNEL_READ_TIMER
;
1284 attr
->subbuf_size
= default_get_kernel_channel_subbuf_size();
1285 attr
->num_subbuf
= DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM
;
1286 attr
->output
= DEFAULT_KERNEL_CHANNEL_OUTPUT
;
1288 case LTTNG_DOMAIN_UST
:
1289 switch (domain
->buf_type
) {
1290 case LTTNG_BUFFER_PER_UID
:
1291 attr
->subbuf_size
= default_get_ust_uid_channel_subbuf_size();
1292 attr
->num_subbuf
= DEFAULT_UST_UID_CHANNEL_SUBBUF_NUM
;
1293 attr
->output
= DEFAULT_UST_UID_CHANNEL_OUTPUT
;
1294 attr
->switch_timer_interval
= DEFAULT_UST_UID_CHANNEL_SWITCH_TIMER
;
1295 attr
->read_timer_interval
= DEFAULT_UST_UID_CHANNEL_READ_TIMER
;
1297 case LTTNG_BUFFER_PER_PID
:
1299 attr
->subbuf_size
= default_get_ust_pid_channel_subbuf_size();
1300 attr
->num_subbuf
= DEFAULT_UST_PID_CHANNEL_SUBBUF_NUM
;
1301 attr
->output
= DEFAULT_UST_PID_CHANNEL_OUTPUT
;
1302 attr
->switch_timer_interval
= DEFAULT_UST_PID_CHANNEL_SWITCH_TIMER
;
1303 attr
->read_timer_interval
= DEFAULT_UST_PID_CHANNEL_READ_TIMER
;
1307 /* Default behavior: leave set to 0. */
1313 * Check if session daemon is alive.
1315 * Return 1 if alive or 0 if not.
1316 * On error returns a negative value.
1318 int lttng_session_daemon_alive(void)
1322 ret
= set_session_daemon_path();
1328 if (*sessiond_sock_path
== '\0') {
1330 * No socket path set. Weird error which means the constructor was not
1336 ret
= try_connect_sessiond(sessiond_sock_path
);
1347 * Set URL for a consumer for a session and domain.
1349 * Return 0 on success, else a negative value.
1351 int lttng_set_consumer_url(struct lttng_handle
*handle
,
1352 const char *control_url
, const char *data_url
)
1356 struct lttcomm_session_msg lsm
;
1357 struct lttng_uri
*uris
= NULL
;
1359 if (handle
== NULL
|| (control_url
== NULL
&& data_url
== NULL
)) {
1360 return -LTTNG_ERR_INVALID
;
1363 memset(&lsm
, 0, sizeof(lsm
));
1365 lsm
.cmd_type
= LTTNG_SET_CONSUMER_URI
;
1367 lttng_ctl_copy_string(lsm
.session
.name
, handle
->session_name
,
1368 sizeof(lsm
.session
.name
));
1369 lttng_ctl_copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1371 size
= uri_parse_str_urls(control_url
, data_url
, &uris
);
1373 return -LTTNG_ERR_INVALID
;
1376 lsm
.u
.uri
.size
= size
;
1378 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1379 sizeof(struct lttng_uri
) * size
, NULL
);
1388 int lttng_enable_consumer(struct lttng_handle
*handle
)
1396 int lttng_disable_consumer(struct lttng_handle
*handle
)
1402 * This is an extension of create session that is ONLY and SHOULD only be used
1403 * by the lttng command line program. It exists to avoid using URI parsing in
1406 * We need the date and time for the trace path subdirectory for the case where
1407 * the user does NOT define one using either -o or -U. Using the normal
1408 * lttng_create_session API call, we have no clue on the session daemon side if
1409 * the URL was generated automatically by the client or define by the user.
1411 * So this function "wrapper" is hidden from the public API, takes the datetime
1412 * string and appends it if necessary to the URI subdirectory before sending it
1413 * to the session daemon.
1415 * With this extra function, the lttng_create_session call behavior is not
1416 * changed and the timestamp is appended to the URI on the session daemon side
1419 int _lttng_create_session_ext(const char *name
, const char *url
,
1420 const char *datetime
)
1424 struct lttcomm_session_msg lsm
;
1425 struct lttng_uri
*uris
= NULL
;
1427 if (name
== NULL
|| datetime
== NULL
) {
1428 return -LTTNG_ERR_INVALID
;
1431 memset(&lsm
, 0, sizeof(lsm
));
1433 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1434 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1436 /* There should never be a data URL */
1437 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1439 ret
= -LTTNG_ERR_INVALID
;
1443 lsm
.u
.uri
.size
= size
;
1445 if (size
> 0 && uris
[0].dtype
!= LTTNG_DST_PATH
&& strlen(uris
[0].subdir
) == 0) {
1446 /* Don't append datetime if the name was automatically created. */
1447 if (strncmp(name
, DEFAULT_SESSION_NAME
"-",
1448 strlen(DEFAULT_SESSION_NAME
) + 1)) {
1449 ret
= snprintf(uris
[0].subdir
, sizeof(uris
[0].subdir
), "%s-%s",
1452 ret
= snprintf(uris
[0].subdir
, sizeof(uris
[0].subdir
), "%s", name
);
1455 PERROR("snprintf uri subdir");
1456 ret
= -LTTNG_ERR_FATAL
;
1461 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1462 sizeof(struct lttng_uri
) * size
, NULL
);
1470 * For a given session name, this call checks if the data is ready to be read
1471 * or is still being extracted by the consumer(s) hence not ready to be used by
1474 int lttng_data_pending(const char *session_name
)
1477 struct lttcomm_session_msg lsm
;
1479 if (session_name
== NULL
) {
1480 return -LTTNG_ERR_INVALID
;
1483 lsm
.cmd_type
= LTTNG_DATA_PENDING
;
1485 lttng_ctl_copy_string(lsm
.session
.name
, session_name
,
1486 sizeof(lsm
.session
.name
));
1488 ret
= lttng_ctl_ask_sessiond(&lsm
, NULL
);
1491 * The lttng_ctl_ask_sessiond function negate the return code if it's not
1492 * LTTNG_OK so getting -1 means that the reply ret_code was 1 thus meaning
1493 * that the data is available. Yes it is hackish but for now this is the
1504 * Create a session exclusively used for snapshot.
1506 * Returns LTTNG_OK on success or a negative error code.
1508 int lttng_create_session_snapshot(const char *name
, const char *snapshot_url
)
1512 struct lttcomm_session_msg lsm
;
1513 struct lttng_uri
*uris
= NULL
;
1516 return -LTTNG_ERR_INVALID
;
1519 memset(&lsm
, 0, sizeof(lsm
));
1521 lsm
.cmd_type
= LTTNG_CREATE_SESSION_SNAPSHOT
;
1522 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1524 size
= uri_parse_str_urls(snapshot_url
, NULL
, &uris
);
1526 return -LTTNG_ERR_INVALID
;
1529 lsm
.u
.uri
.size
= size
;
1531 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1532 sizeof(struct lttng_uri
) * size
, NULL
);
1539 * Create a session exclusively used for live.
1541 * Returns LTTNG_OK on success or a negative error code.
1543 int lttng_create_session_live(const char *name
, const char *url
,
1544 unsigned int timer_interval
)
1548 struct lttcomm_session_msg lsm
;
1549 struct lttng_uri
*uris
= NULL
;
1552 return -LTTNG_ERR_INVALID
;
1555 memset(&lsm
, 0, sizeof(lsm
));
1557 lsm
.cmd_type
= LTTNG_CREATE_SESSION_LIVE
;
1558 lttng_ctl_copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1560 size
= uri_parse_str_urls(url
, NULL
, &uris
);
1562 ret
= -LTTNG_ERR_INVALID
;
1566 /* file:// is not accepted for live session. */
1567 if (uris
[0].dtype
== LTTNG_DST_PATH
) {
1568 ret
= -LTTNG_ERR_INVALID
;
1572 lsm
.u
.session_live
.nb_uri
= size
;
1573 lsm
.u
.session_live
.timer_interval
= timer_interval
;
1575 ret
= lttng_ctl_ask_sessiond_varlen(&lsm
, uris
,
1576 sizeof(struct lttng_uri
) * size
, NULL
);
1586 static void __attribute__((constructor
)) init()
1588 /* Set default session group */
1589 lttng_set_tracing_group(DEFAULT_TRACING_GROUP
);
1595 static void __attribute__((destructor
)) lttng_ctl_exit()
1597 free(tracing_group
);