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 <lttng/lttng.h>
37 #include "filter/filter-ast.h"
38 #include "filter/filter-parser.h"
39 #include "filter/filter-bytecode.h"
40 #include "filter/memstream.h"
43 static const int print_xml
= 1;
44 #define dbg_printf(fmt, args...) \
45 printf("[debug liblttng-ctl] " fmt, ## args)
47 static const int print_xml
= 0;
48 #define dbg_printf(fmt, args...) \
50 /* do nothing but check printf format */ \
52 printf("[debug liblttnctl] " fmt, ## args); \
57 /* Socket to session daemon for communication */
58 static int sessiond_socket
;
59 static char sessiond_sock_path
[PATH_MAX
];
60 static char health_sock_path
[PATH_MAX
];
63 static char *tracing_group
;
69 * Those two variables are used by error.h to silent or control the verbosity of
70 * error message. They are global to the library so application linking with it
71 * are able to compile correctly and also control verbosity of the library.
74 int lttng_opt_verbose
;
76 static void set_default_url_attr(struct lttng_uri
*uri
,
77 enum lttng_stream_type stype
)
80 if (uri
->dtype
!= LTTNG_DST_PATH
&& uri
->port
== 0) {
81 uri
->port
= (stype
== LTTNG_STREAM_CONTROL
) ?
82 DEFAULT_NETWORK_CONTROL_PORT
: DEFAULT_NETWORK_DATA_PORT
;
87 * Parse a string URL and creates URI(s) returning the size of the populated
90 static ssize_t
parse_str_urls_to_uri(const char *ctrl_url
, const char *data_url
,
91 struct lttng_uri
**uris
)
94 unsigned int equal
= 1, idx
= 0;
95 /* Add the "file://" size to the URL maximum size */
96 char url
[PATH_MAX
+ 7];
97 ssize_t size_ctrl
= 0, size_data
= 0, size
;
98 struct lttng_uri
*ctrl_uris
= NULL
, *data_uris
= NULL
;
99 struct lttng_uri
*tmp_uris
= NULL
;
101 /* No URL(s) is allowed. This means that the consumer will be disabled. */
102 if (ctrl_url
== NULL
&& data_url
== NULL
) {
106 /* Check if URLs are equal and if so, only use the control URL */
107 if (ctrl_url
&& data_url
) {
108 equal
= !strcmp(ctrl_url
, data_url
);
112 * Since we allow the str_url to be a full local filesystem path, we are
113 * going to create a valid file:// URL if it's the case.
115 * Check if first character is a '/' or else reject the URL.
117 if (ctrl_url
&& ctrl_url
[0] == '/') {
118 ret
= snprintf(url
, sizeof(url
), "file://%s", ctrl_url
);
120 PERROR("snprintf file url");
126 /* Parse the control URL if there is one */
128 size_ctrl
= uri_parse(ctrl_url
, &ctrl_uris
);
130 ERR("Unable to parse the URL %s", ctrl_url
);
134 /* At this point, we know there is at least one URI in the array */
135 set_default_url_attr(&ctrl_uris
[0], LTTNG_STREAM_CONTROL
);
137 if (ctrl_uris
[0].dtype
== LTTNG_DST_PATH
&& data_url
) {
138 ERR("Can not have a data URL when destination is file://");
142 /* URL are not equal but the control URL uses a net:// protocol */
143 if (size_ctrl
== 2) {
145 ERR("Control URL uses the net:// protocol and the data URL is "
146 "different. Not allowed.");
149 set_default_url_attr(&ctrl_uris
[1], LTTNG_STREAM_DATA
);
151 * The data_url and ctrl_url are equal and the ctrl_url
152 * contains a net:// protocol so we just skip the data part.
160 /* We have to parse the data URL in this case */
161 size_data
= uri_parse(data_url
, &data_uris
);
163 ERR("Unable to parse the URL %s", data_url
);
165 } else if (size_data
== 2) {
166 ERR("Data URL can not be set with the net[4|6]:// protocol");
170 set_default_url_attr(&data_uris
[0], LTTNG_STREAM_DATA
);
173 /* Compute total size */
174 size
= size_ctrl
+ size_data
;
176 tmp_uris
= zmalloc(sizeof(struct lttng_uri
) * size
);
177 if (tmp_uris
== NULL
) {
178 PERROR("zmalloc uris");
183 /* It's possible the control URIs array contains more than one URI */
184 memcpy(tmp_uris
, ctrl_uris
, sizeof(struct lttng_uri
) * size_ctrl
);
189 memcpy(&tmp_uris
[idx
], data_uris
, sizeof(struct lttng_uri
));
205 * Copy string from src to dst and enforce null terminated byte.
207 static void copy_string(char *dst
, const char *src
, size_t len
)
210 strncpy(dst
, src
, len
);
211 /* Enforce the NULL terminated byte */
219 * Copy domain to lttcomm_session_msg domain.
221 * If domain is unknown, default domain will be the kernel.
223 static void copy_lttng_domain(struct lttng_domain
*dst
, struct lttng_domain
*src
)
227 case LTTNG_DOMAIN_KERNEL
:
228 case LTTNG_DOMAIN_UST
:
230 case LTTNG_DOMAIN_UST_EXEC_NAME:
231 case LTTNG_DOMAIN_UST_PID:
232 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
234 memcpy(dst
, src
, sizeof(struct lttng_domain
));
237 memset(dst
, 0, sizeof(struct lttng_domain
));
244 * Send lttcomm_session_msg to the session daemon.
246 * On success, returns the number of bytes sent (>=0)
247 * On error, returns -1
249 static int send_session_msg(struct lttcomm_session_msg
*lsm
)
254 ret
= -LTTNG_ERR_NO_SESSIOND
;
258 DBG("LSM cmd type : %d", lsm
->cmd_type
);
260 ret
= lttcomm_send_creds_unix_sock(sessiond_socket
, lsm
,
261 sizeof(struct lttcomm_session_msg
));
263 ret
= -LTTNG_ERR_FATAL
;
271 * Send var len data to the session daemon.
273 * On success, returns the number of bytes sent (>=0)
274 * On error, returns -1
276 static int send_session_varlen(void *data
, size_t len
)
281 ret
= -LTTNG_ERR_NO_SESSIOND
;
290 ret
= lttcomm_send_unix_sock(sessiond_socket
, data
, len
);
292 ret
= -LTTNG_ERR_FATAL
;
300 * Receive data from the sessiond socket.
302 * On success, returns the number of bytes received (>=0)
303 * On error, returns -1 (recvmsg() error) or -ENOTCONN
305 static int recv_data_sessiond(void *buf
, size_t len
)
310 ret
= -LTTNG_ERR_NO_SESSIOND
;
314 ret
= lttcomm_recv_unix_sock(sessiond_socket
, buf
, len
);
316 ret
= -LTTNG_ERR_FATAL
;
324 * Check if we are in the specified group.
326 * If yes return 1, else return -1.
328 static int check_tracing_group(const char *grp_name
)
330 struct group
*grp_tracing
; /* no free(). See getgrnam(3) */
332 int grp_list_size
, grp_id
, i
;
335 /* Get GID of group 'tracing' */
336 grp_tracing
= getgrnam(grp_name
);
338 /* If grp_tracing is NULL, the group does not exist. */
342 /* Get number of supplementary group IDs */
343 grp_list_size
= getgroups(0, NULL
);
344 if (grp_list_size
< 0) {
349 /* Alloc group list of the right size */
350 grp_list
= malloc(grp_list_size
* sizeof(gid_t
));
355 grp_id
= getgroups(grp_list_size
, grp_list
);
361 for (i
= 0; i
< grp_list_size
; i
++) {
362 if (grp_list
[i
] == grp_tracing
->gr_gid
) {
376 * Try connect to session daemon with sock_path.
378 * Return 0 on success, else -1
380 static int try_connect_sessiond(const char *sock_path
)
384 /* If socket exist, we check if the daemon listens for connect. */
385 ret
= access(sock_path
, F_OK
);
391 ret
= lttcomm_connect_unix_sock(sock_path
);
397 ret
= lttcomm_close_unix_sock(ret
);
399 perror("lttcomm_close_unix_sock");
409 * Set sessiond socket path by putting it in the global sessiond_sock_path
412 * Returns 0 on success, negative value on failure (the sessiond socket path
413 * is somehow too long or ENOMEM).
415 static int set_session_daemon_path(void)
418 int in_tgroup
= 0; /* In tracing group */
424 /* Are we in the tracing group ? */
425 in_tgroup
= check_tracing_group(tracing_group
);
428 if ((uid
== 0) || in_tgroup
) {
429 copy_string(sessiond_sock_path
, DEFAULT_GLOBAL_CLIENT_UNIX_SOCK
,
430 sizeof(sessiond_sock_path
));
436 ret
= try_connect_sessiond(sessiond_sock_path
);
440 /* Global session daemon not available... */
442 /* ...or not in tracing group (and not root), default */
445 * With GNU C < 2.1, snprintf returns -1 if the target buffer is too small;
446 * With GNU C >= 2.1, snprintf returns the required size (excluding closing null)
448 ret
= snprintf(sessiond_sock_path
, sizeof(sessiond_sock_path
),
449 DEFAULT_HOME_CLIENT_UNIX_SOCK
, getenv("HOME"));
450 if ((ret
< 0) || (ret
>= sizeof(sessiond_sock_path
))) {
462 * Connect to the LTTng session daemon.
464 * On success, return 0. On error, return -1.
466 static int connect_sessiond(void)
470 ret
= set_session_daemon_path();
475 /* Connect to the sesssion daemon */
476 ret
= lttcomm_connect_unix_sock(sessiond_sock_path
);
481 sessiond_socket
= ret
;
491 * Clean disconnect from the session daemon.
492 * On success, return 0. On error, return -1.
494 static int disconnect_sessiond(void)
499 ret
= lttcomm_close_unix_sock(sessiond_socket
);
508 * Ask the session daemon a specific command and put the data into buf.
509 * Takes extra var. len. data as input to send to the session daemon.
511 * Return size of data (only payload, not header) or a negative error code.
513 static int ask_sessiond_varlen(struct lttcomm_session_msg
*lsm
,
514 void *vardata
, size_t varlen
, void **buf
)
519 struct lttcomm_lttng_msg llm
;
521 ret
= connect_sessiond();
523 ret
= -LTTNG_ERR_NO_SESSIOND
;
527 /* Send command to session daemon */
528 ret
= send_session_msg(lsm
);
530 /* Ret value is a valid lttng error code. */
533 /* Send var len data */
534 ret
= send_session_varlen(vardata
, varlen
);
536 /* Ret value is a valid lttng error code. */
540 /* Get header from data transmission */
541 ret
= recv_data_sessiond(&llm
, sizeof(llm
));
543 /* Ret value is a valid lttng error code. */
547 /* Check error code if OK */
548 if (llm
.ret_code
!= LTTNG_OK
) {
553 size
= llm
.data_size
;
555 /* If client free with size 0 */
563 data
= (void*) malloc(size
);
565 /* Get payload data */
566 ret
= recv_data_sessiond(data
, size
);
573 * Extra protection not to dereference a NULL pointer. If buf is NULL at
574 * this point, an error is returned and data is freed.
577 ret
= -LTTNG_ERR_INVALID
;
586 disconnect_sessiond();
591 * Ask the session daemon a specific command and put the data into buf.
593 * Return size of data (only payload, not header) or a negative error code.
595 static int ask_sessiond(struct lttcomm_session_msg
*lsm
, void **buf
)
597 return ask_sessiond_varlen(lsm
, NULL
, 0, buf
);
601 * Create lttng handle and return pointer.
602 * The returned pointer will be NULL in case of malloc() error.
604 struct lttng_handle
*lttng_create_handle(const char *session_name
,
605 struct lttng_domain
*domain
)
607 struct lttng_handle
*handle
= NULL
;
609 if (domain
== NULL
) {
613 handle
= malloc(sizeof(struct lttng_handle
));
614 if (handle
== NULL
) {
615 PERROR("malloc handle");
619 /* Copy session name */
620 copy_string(handle
->session_name
, session_name
,
621 sizeof(handle
->session_name
));
623 /* Copy lttng domain */
624 copy_lttng_domain(&handle
->domain
, domain
);
631 * Destroy handle by free(3) the pointer.
633 void lttng_destroy_handle(struct lttng_handle
*handle
)
641 * Register an outside consumer.
642 * Returns size of returned session payload data or a negative error code.
644 int lttng_register_consumer(struct lttng_handle
*handle
,
645 const char *socket_path
)
647 struct lttcomm_session_msg lsm
;
649 if (handle
== NULL
|| socket_path
== NULL
) {
650 return -LTTNG_ERR_INVALID
;
653 lsm
.cmd_type
= LTTNG_REGISTER_CONSUMER
;
654 copy_string(lsm
.session
.name
, handle
->session_name
,
655 sizeof(lsm
.session
.name
));
656 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
658 copy_string(lsm
.u
.reg
.path
, socket_path
, sizeof(lsm
.u
.reg
.path
));
660 return ask_sessiond(&lsm
, NULL
);
664 * Start tracing for all traces of the session.
665 * Returns size of returned session payload data or a negative error code.
667 int lttng_start_tracing(const char *session_name
)
669 struct lttcomm_session_msg lsm
;
671 if (session_name
== NULL
) {
672 return -LTTNG_ERR_INVALID
;
675 lsm
.cmd_type
= LTTNG_START_TRACE
;
677 copy_string(lsm
.session
.name
, session_name
, sizeof(lsm
.session
.name
));
679 return ask_sessiond(&lsm
, NULL
);
683 * Stop tracing for all traces of the session.
685 static int _lttng_stop_tracing(const char *session_name
, int wait
)
688 struct lttcomm_session_msg lsm
;
690 if (session_name
== NULL
) {
691 return -LTTNG_ERR_INVALID
;
694 lsm
.cmd_type
= LTTNG_STOP_TRACE
;
696 copy_string(lsm
.session
.name
, session_name
, sizeof(lsm
.session
.name
));
698 ret
= ask_sessiond(&lsm
, NULL
);
699 if (ret
< 0 && ret
!= -LTTNG_ERR_TRACE_ALREADY_STOPPED
) {
707 _MSG("Waiting for data availability");
709 /* Check for data availability */
711 data_ret
= lttng_data_pending(session_name
);
713 /* Return the data available call error. */
719 * Data sleep time before retrying (in usec). Don't sleep if the call
720 * returned value indicates availability.
723 usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME
);
726 } while (data_ret
!= 0);
736 * Stop tracing and wait for data availability.
738 int lttng_stop_tracing(const char *session_name
)
740 return _lttng_stop_tracing(session_name
, 1);
744 * Stop tracing but _don't_ wait for data availability.
746 int lttng_stop_tracing_no_wait(const char *session_name
)
748 return _lttng_stop_tracing(session_name
, 0);
752 * Add context to event and/or channel.
753 * If event_name is NULL, the context is applied to all events of the channel.
754 * If channel_name is NULL, a lookup of the event's channel is done.
755 * If both are NULL, the context is applied to all events of all channels.
757 * Returns the size of the returned payload data or a negative error code.
759 int lttng_add_context(struct lttng_handle
*handle
,
760 struct lttng_event_context
*ctx
, const char *event_name
,
761 const char *channel_name
)
763 struct lttcomm_session_msg lsm
;
765 /* Safety check. Both are mandatory */
766 if (handle
== NULL
|| ctx
== NULL
) {
767 return -LTTNG_ERR_INVALID
;
770 memset(&lsm
, 0, sizeof(lsm
));
772 lsm
.cmd_type
= LTTNG_ADD_CONTEXT
;
774 /* Copy channel name */
775 copy_string(lsm
.u
.context
.channel_name
, channel_name
,
776 sizeof(lsm
.u
.context
.channel_name
));
777 /* Copy event name */
778 copy_string(lsm
.u
.context
.event_name
, event_name
,
779 sizeof(lsm
.u
.context
.event_name
));
781 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
783 memcpy(&lsm
.u
.context
.ctx
, ctx
, sizeof(struct lttng_event_context
));
785 copy_string(lsm
.session
.name
, handle
->session_name
,
786 sizeof(lsm
.session
.name
));
788 return ask_sessiond(&lsm
, NULL
);
792 * Enable event(s) for a channel.
793 * If no event name is specified, all events are enabled.
794 * If no channel name is specified, the default 'channel0' is used.
795 * Returns size of returned session payload data or a negative error code.
797 int lttng_enable_event(struct lttng_handle
*handle
,
798 struct lttng_event
*ev
, const char *channel_name
)
800 struct lttcomm_session_msg lsm
;
802 if (handle
== NULL
|| ev
== NULL
) {
803 return -LTTNG_ERR_INVALID
;
806 memset(&lsm
, 0, sizeof(lsm
));
808 /* If no channel name, we put the default name */
809 if (channel_name
== NULL
) {
810 copy_string(lsm
.u
.enable
.channel_name
, DEFAULT_CHANNEL_NAME
,
811 sizeof(lsm
.u
.enable
.channel_name
));
813 copy_string(lsm
.u
.enable
.channel_name
, channel_name
,
814 sizeof(lsm
.u
.enable
.channel_name
));
817 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
819 if (ev
->name
[0] != '\0') {
820 lsm
.cmd_type
= LTTNG_ENABLE_EVENT
;
822 lsm
.cmd_type
= LTTNG_ENABLE_ALL_EVENT
;
824 memcpy(&lsm
.u
.enable
.event
, ev
, sizeof(lsm
.u
.enable
.event
));
826 copy_string(lsm
.session
.name
, handle
->session_name
,
827 sizeof(lsm
.session
.name
));
829 return ask_sessiond(&lsm
, NULL
);
833 * set filter for an event
834 * Return negative error value on error.
835 * Return size of returned session payload data if OK.
838 int lttng_set_event_filter(struct lttng_handle
*handle
,
839 const char *event_name
, const char *channel_name
,
840 const char *filter_expression
)
842 struct lttcomm_session_msg lsm
;
843 struct filter_parser_ctx
*ctx
;
848 if (handle
== NULL
) {
849 return -LTTNG_ERR_INVALID
;
852 if (!filter_expression
) {
857 * casting const to non-const, as the underlying function will
858 * use it in read-only mode.
860 fmem
= lttng_fmemopen((void *) filter_expression
,
861 strlen(filter_expression
), "r");
863 fprintf(stderr
, "Error opening memory as stream\n");
864 return -LTTNG_ERR_FILTER_NOMEM
;
866 ctx
= filter_parser_ctx_alloc(fmem
);
868 fprintf(stderr
, "Error allocating parser\n");
869 ret
= -LTTNG_ERR_FILTER_NOMEM
;
872 ret
= filter_parser_ctx_append_ast(ctx
);
874 fprintf(stderr
, "Parse error\n");
875 ret
= -LTTNG_ERR_FILTER_INVAL
;
878 ret
= filter_visitor_set_parent(ctx
);
880 fprintf(stderr
, "Set parent error\n");
881 ret
= -LTTNG_ERR_FILTER_INVAL
;
885 ret
= filter_visitor_print_xml(ctx
, stdout
, 0);
888 fprintf(stderr
, "XML print error\n");
889 ret
= -LTTNG_ERR_FILTER_INVAL
;
894 dbg_printf("Generating IR... ");
896 ret
= filter_visitor_ir_generate(ctx
);
898 fprintf(stderr
, "Generate IR error\n");
899 ret
= -LTTNG_ERR_FILTER_INVAL
;
902 dbg_printf("done\n");
904 dbg_printf("Validating IR... ");
906 ret
= filter_visitor_ir_check_binary_op_nesting(ctx
);
908 ret
= -LTTNG_ERR_FILTER_INVAL
;
911 dbg_printf("done\n");
913 dbg_printf("Generating bytecode... ");
915 ret
= filter_visitor_bytecode_generate(ctx
);
917 fprintf(stderr
, "Generate bytecode error\n");
918 ret
= -LTTNG_ERR_FILTER_INVAL
;
921 dbg_printf("done\n");
922 dbg_printf("Size of bytecode generated: %u bytes.\n",
923 bytecode_get_len(&ctx
->bytecode
->b
));
925 memset(&lsm
, 0, sizeof(lsm
));
927 lsm
.cmd_type
= LTTNG_SET_FILTER
;
929 /* Copy channel name */
930 copy_string(lsm
.u
.filter
.channel_name
, channel_name
,
931 sizeof(lsm
.u
.filter
.channel_name
));
932 /* Copy event name */
933 copy_string(lsm
.u
.filter
.event_name
, event_name
,
934 sizeof(lsm
.u
.filter
.event_name
));
935 lsm
.u
.filter
.bytecode_len
= sizeof(ctx
->bytecode
->b
)
936 + bytecode_get_len(&ctx
->bytecode
->b
);
938 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
940 copy_string(lsm
.session
.name
, handle
->session_name
,
941 sizeof(lsm
.session
.name
));
943 ret
= ask_sessiond_varlen(&lsm
, &ctx
->bytecode
->b
,
944 lsm
.u
.filter
.bytecode_len
, NULL
);
946 filter_bytecode_free(ctx
);
948 filter_parser_ctx_free(ctx
);
949 if (fclose(fmem
) != 0) {
955 filter_bytecode_free(ctx
);
957 filter_parser_ctx_free(ctx
);
959 if (fclose(fmem
) != 0) {
966 * Disable event(s) of a channel and domain.
967 * If no event name is specified, all events are disabled.
968 * If no channel name is specified, the default 'channel0' is used.
969 * Returns size of returned session payload data or a negative error code.
971 int lttng_disable_event(struct lttng_handle
*handle
, const char *name
,
972 const char *channel_name
)
974 struct lttcomm_session_msg lsm
;
976 if (handle
== NULL
) {
977 return -LTTNG_ERR_INVALID
;
980 memset(&lsm
, 0, sizeof(lsm
));
983 copy_string(lsm
.u
.disable
.channel_name
, channel_name
,
984 sizeof(lsm
.u
.disable
.channel_name
));
986 copy_string(lsm
.u
.disable
.channel_name
, DEFAULT_CHANNEL_NAME
,
987 sizeof(lsm
.u
.disable
.channel_name
));
990 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
993 copy_string(lsm
.u
.disable
.name
, name
, sizeof(lsm
.u
.disable
.name
));
994 lsm
.cmd_type
= LTTNG_DISABLE_EVENT
;
996 lsm
.cmd_type
= LTTNG_DISABLE_ALL_EVENT
;
999 copy_string(lsm
.session
.name
, handle
->session_name
,
1000 sizeof(lsm
.session
.name
));
1002 return ask_sessiond(&lsm
, NULL
);
1006 * Enable channel per domain
1007 * Returns size of returned session payload data or a negative error code.
1009 int lttng_enable_channel(struct lttng_handle
*handle
,
1010 struct lttng_channel
*chan
)
1012 struct lttcomm_session_msg lsm
;
1015 * NULL arguments are forbidden. No default values.
1017 if (handle
== NULL
|| chan
== NULL
) {
1018 return -LTTNG_ERR_INVALID
;
1021 memset(&lsm
, 0, sizeof(lsm
));
1023 memcpy(&lsm
.u
.channel
.chan
, chan
, sizeof(lsm
.u
.channel
.chan
));
1025 lsm
.cmd_type
= LTTNG_ENABLE_CHANNEL
;
1027 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1029 copy_string(lsm
.session
.name
, handle
->session_name
,
1030 sizeof(lsm
.session
.name
));
1032 return ask_sessiond(&lsm
, NULL
);
1036 * All tracing will be stopped for registered events of the channel.
1037 * Returns size of returned session payload data or a negative error code.
1039 int lttng_disable_channel(struct lttng_handle
*handle
, const char *name
)
1041 struct lttcomm_session_msg lsm
;
1043 /* Safety check. Both are mandatory */
1044 if (handle
== NULL
|| name
== NULL
) {
1045 return -LTTNG_ERR_INVALID
;
1048 memset(&lsm
, 0, sizeof(lsm
));
1050 lsm
.cmd_type
= LTTNG_DISABLE_CHANNEL
;
1052 copy_string(lsm
.u
.disable
.channel_name
, name
,
1053 sizeof(lsm
.u
.disable
.channel_name
));
1055 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1057 copy_string(lsm
.session
.name
, handle
->session_name
,
1058 sizeof(lsm
.session
.name
));
1060 return ask_sessiond(&lsm
, NULL
);
1064 * Lists all available tracepoints of domain.
1065 * Sets the contents of the events array.
1066 * Returns the number of lttng_event entries in events;
1067 * on error, returns a negative value.
1069 int lttng_list_tracepoints(struct lttng_handle
*handle
,
1070 struct lttng_event
**events
)
1073 struct lttcomm_session_msg lsm
;
1075 if (handle
== NULL
) {
1076 return -LTTNG_ERR_INVALID
;
1079 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINTS
;
1080 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1082 ret
= ask_sessiond(&lsm
, (void **) events
);
1087 return ret
/ sizeof(struct lttng_event
);
1091 * Lists all available tracepoint fields of domain.
1092 * Sets the contents of the event field array.
1093 * Returns the number of lttng_event_field entries in events;
1094 * on error, returns a negative value.
1096 int lttng_list_tracepoint_fields(struct lttng_handle
*handle
,
1097 struct lttng_event_field
**fields
)
1100 struct lttcomm_session_msg lsm
;
1102 if (handle
== NULL
) {
1103 return -LTTNG_ERR_INVALID
;
1106 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINT_FIELDS
;
1107 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1109 ret
= ask_sessiond(&lsm
, (void **) fields
);
1114 return ret
/ sizeof(struct lttng_event_field
);
1118 * Returns a human readable string describing
1119 * the error code (a negative value).
1121 const char *lttng_strerror(int code
)
1123 return error_get_str(code
);
1127 * Create a brand new session using name and url for destination.
1129 * Returns LTTNG_OK on success or a negative error code.
1131 int lttng_create_session(const char *name
, const char *url
)
1134 struct lttcomm_session_msg lsm
;
1135 struct lttng_uri
*uris
= NULL
;
1138 return -LTTNG_ERR_INVALID
;
1141 memset(&lsm
, 0, sizeof(lsm
));
1143 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1144 copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1146 /* There should never be a data URL */
1147 size
= parse_str_urls_to_uri(url
, NULL
, &uris
);
1149 return -LTTNG_ERR_INVALID
;
1152 lsm
.u
.uri
.size
= size
;
1154 return ask_sessiond_varlen(&lsm
, uris
, sizeof(struct lttng_uri
) * size
,
1159 * Destroy session using name.
1160 * Returns size of returned session payload data or a negative error code.
1162 int lttng_destroy_session(const char *session_name
)
1164 struct lttcomm_session_msg lsm
;
1166 if (session_name
== NULL
) {
1167 return -LTTNG_ERR_INVALID
;
1170 lsm
.cmd_type
= LTTNG_DESTROY_SESSION
;
1172 copy_string(lsm
.session
.name
, session_name
, sizeof(lsm
.session
.name
));
1174 return ask_sessiond(&lsm
, NULL
);
1178 * Ask the session daemon for all available sessions.
1179 * Sets the contents of the sessions array.
1180 * Returns the number of lttng_session entries in sessions;
1181 * on error, returns a negative value.
1183 int lttng_list_sessions(struct lttng_session
**sessions
)
1186 struct lttcomm_session_msg lsm
;
1188 lsm
.cmd_type
= LTTNG_LIST_SESSIONS
;
1189 ret
= ask_sessiond(&lsm
, (void**) sessions
);
1194 return ret
/ sizeof(struct lttng_session
);
1198 * Ask the session daemon for all available domains of a session.
1199 * Sets the contents of the domains array.
1200 * Returns the number of lttng_domain entries in domains;
1201 * on error, returns a negative value.
1203 int lttng_list_domains(const char *session_name
,
1204 struct lttng_domain
**domains
)
1207 struct lttcomm_session_msg lsm
;
1209 if (session_name
== NULL
) {
1210 return -LTTNG_ERR_INVALID
;
1213 lsm
.cmd_type
= LTTNG_LIST_DOMAINS
;
1215 copy_string(lsm
.session
.name
, session_name
, sizeof(lsm
.session
.name
));
1217 ret
= ask_sessiond(&lsm
, (void**) domains
);
1222 return ret
/ sizeof(struct lttng_domain
);
1226 * Ask the session daemon for all available channels of a session.
1227 * Sets the contents of the channels array.
1228 * Returns the number of lttng_channel entries in channels;
1229 * on error, returns a negative value.
1231 int lttng_list_channels(struct lttng_handle
*handle
,
1232 struct lttng_channel
**channels
)
1235 struct lttcomm_session_msg lsm
;
1237 if (handle
== NULL
) {
1238 return -LTTNG_ERR_INVALID
;
1241 lsm
.cmd_type
= LTTNG_LIST_CHANNELS
;
1242 copy_string(lsm
.session
.name
, handle
->session_name
,
1243 sizeof(lsm
.session
.name
));
1245 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1247 ret
= ask_sessiond(&lsm
, (void**) channels
);
1252 return ret
/ sizeof(struct lttng_channel
);
1256 * Ask the session daemon for all available events of a session channel.
1257 * Sets the contents of the events array.
1258 * Returns the number of lttng_event entries in events;
1259 * on error, returns a negative value.
1261 int lttng_list_events(struct lttng_handle
*handle
,
1262 const char *channel_name
, struct lttng_event
**events
)
1265 struct lttcomm_session_msg lsm
;
1267 /* Safety check. An handle and channel name are mandatory */
1268 if (handle
== NULL
|| channel_name
== NULL
) {
1269 return -LTTNG_ERR_INVALID
;
1272 lsm
.cmd_type
= LTTNG_LIST_EVENTS
;
1273 copy_string(lsm
.session
.name
, handle
->session_name
,
1274 sizeof(lsm
.session
.name
));
1275 copy_string(lsm
.u
.list
.channel_name
, channel_name
,
1276 sizeof(lsm
.u
.list
.channel_name
));
1278 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1280 ret
= ask_sessiond(&lsm
, (void**) events
);
1285 return ret
/ sizeof(struct lttng_event
);
1289 * Sets the tracing_group variable with name.
1290 * This function allocates memory pointed to by tracing_group.
1291 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
1293 int lttng_set_tracing_group(const char *name
)
1296 return -LTTNG_ERR_INVALID
;
1299 if (asprintf(&tracing_group
, "%s", name
) < 0) {
1300 return -LTTNG_ERR_FATAL
;
1307 * Returns size of returned session payload data or a negative error code.
1309 int lttng_calibrate(struct lttng_handle
*handle
,
1310 struct lttng_calibrate
*calibrate
)
1312 struct lttcomm_session_msg lsm
;
1314 /* Safety check. NULL pointer are forbidden */
1315 if (handle
== NULL
|| calibrate
== NULL
) {
1316 return -LTTNG_ERR_INVALID
;
1319 lsm
.cmd_type
= LTTNG_CALIBRATE
;
1320 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1322 memcpy(&lsm
.u
.calibrate
, calibrate
, sizeof(lsm
.u
.calibrate
));
1324 return ask_sessiond(&lsm
, NULL
);
1328 * Set default channel attributes.
1329 * If either or both of the arguments are null, attr content is zeroe'd.
1331 void lttng_channel_set_default_attr(struct lttng_domain
*domain
,
1332 struct lttng_channel_attr
*attr
)
1335 if (attr
== NULL
|| domain
== NULL
) {
1339 memset(attr
, 0, sizeof(struct lttng_channel_attr
));
1341 switch (domain
->type
) {
1342 case LTTNG_DOMAIN_KERNEL
:
1343 attr
->overwrite
= DEFAULT_CHANNEL_OVERWRITE
;
1344 attr
->switch_timer_interval
= DEFAULT_CHANNEL_SWITCH_TIMER
;
1345 attr
->read_timer_interval
= DEFAULT_CHANNEL_READ_TIMER
;
1347 attr
->subbuf_size
= default_get_kernel_channel_subbuf_size();
1348 attr
->num_subbuf
= DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM
;
1349 attr
->output
= DEFAULT_KERNEL_CHANNEL_OUTPUT
;
1351 case LTTNG_DOMAIN_UST
:
1353 case LTTNG_DOMAIN_UST_EXEC_NAME
:
1354 case LTTNG_DOMAIN_UST_PID
:
1355 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN
:
1357 attr
->overwrite
= DEFAULT_CHANNEL_OVERWRITE
;
1358 attr
->switch_timer_interval
= DEFAULT_CHANNEL_SWITCH_TIMER
;
1359 attr
->read_timer_interval
= DEFAULT_CHANNEL_READ_TIMER
;
1361 attr
->subbuf_size
= default_get_ust_channel_subbuf_size();
1362 attr
->num_subbuf
= DEFAULT_UST_CHANNEL_SUBBUF_NUM
;
1363 attr
->output
= DEFAULT_UST_CHANNEL_OUTPUT
;
1366 /* Default behavior: leave set to 0. */
1372 * Check if session daemon is alive.
1374 * Return 1 if alive or 0 if not.
1375 * On error returns a negative value.
1377 int lttng_session_daemon_alive(void)
1381 ret
= set_session_daemon_path();
1387 if (strlen(sessiond_sock_path
) == 0) {
1389 * No socket path set. Weird error which means the constructor was not
1395 ret
= try_connect_sessiond(sessiond_sock_path
);
1406 * Set URL for a consumer for a session and domain.
1408 * Return 0 on success, else a negative value.
1410 int lttng_set_consumer_url(struct lttng_handle
*handle
,
1411 const char *control_url
, const char *data_url
)
1414 struct lttcomm_session_msg lsm
;
1415 struct lttng_uri
*uris
= NULL
;
1417 if (handle
== NULL
|| (control_url
== NULL
&& data_url
== NULL
)) {
1418 return -LTTNG_ERR_INVALID
;
1421 memset(&lsm
, 0, sizeof(lsm
));
1423 lsm
.cmd_type
= LTTNG_SET_CONSUMER_URI
;
1425 copy_string(lsm
.session
.name
, handle
->session_name
,
1426 sizeof(lsm
.session
.name
));
1427 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1429 size
= parse_str_urls_to_uri(control_url
, data_url
, &uris
);
1431 return -LTTNG_ERR_INVALID
;
1434 lsm
.u
.uri
.size
= size
;
1436 return ask_sessiond_varlen(&lsm
, uris
, sizeof(struct lttng_uri
) * size
,
1441 * Enable consumer for a session and domain.
1443 * Return 0 on success, else a negative value.
1445 int lttng_enable_consumer(struct lttng_handle
*handle
)
1447 struct lttcomm_session_msg lsm
;
1449 if (handle
== NULL
) {
1450 return -LTTNG_ERR_INVALID
;
1453 lsm
.cmd_type
= LTTNG_ENABLE_CONSUMER
;
1455 copy_string(lsm
.session
.name
, handle
->session_name
,
1456 sizeof(lsm
.session
.name
));
1457 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1459 return ask_sessiond(&lsm
, NULL
);
1463 * Disable consumer for a session and domain.
1465 * Return 0 on success, else a negative value.
1467 int lttng_disable_consumer(struct lttng_handle
*handle
)
1469 struct lttcomm_session_msg lsm
;
1471 if (handle
== NULL
) {
1472 return -LTTNG_ERR_INVALID
;
1475 lsm
.cmd_type
= LTTNG_DISABLE_CONSUMER
;
1477 copy_string(lsm
.session
.name
, handle
->session_name
,
1478 sizeof(lsm
.session
.name
));
1479 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1481 return ask_sessiond(&lsm
, NULL
);
1485 * Set health socket path by putting it in the global health_sock_path
1488 * Returns 0 on success or assert(0) on ENOMEM.
1490 static int set_health_socket_path(void)
1493 int in_tgroup
= 0; /* In tracing group */
1500 /* Are we in the tracing group ? */
1501 in_tgroup
= check_tracing_group(tracing_group
);
1504 if ((uid
== 0) || in_tgroup
) {
1505 copy_string(health_sock_path
, DEFAULT_GLOBAL_HEALTH_UNIX_SOCK
,
1506 sizeof(health_sock_path
));
1511 * With GNU C < 2.1, snprintf returns -1 if the target buffer is too small;
1512 * With GNU C >= 2.1, snprintf returns the required size (excluding closing null)
1514 home
= getenv("HOME");
1516 /* Fallback in /tmp .. */
1520 ret
= snprintf(health_sock_path
, sizeof(health_sock_path
),
1521 DEFAULT_HOME_HEALTH_UNIX_SOCK
, home
);
1522 if ((ret
< 0) || (ret
>= sizeof(health_sock_path
))) {
1523 /* ENOMEM at this point... just kill the control lib. */
1532 * Check session daemon health for a specific health component.
1534 * Return 0 if health is OK or else 1 if BAD.
1536 * Any other negative value is a lttng error code which can be translated with
1539 int lttng_health_check(enum lttng_health_component c
)
1542 struct lttcomm_health_msg msg
;
1543 struct lttcomm_health_data reply
;
1545 /* Connect to the sesssion daemon */
1546 sock
= lttcomm_connect_unix_sock(health_sock_path
);
1548 ret
= -LTTNG_ERR_NO_SESSIOND
;
1552 msg
.cmd
= LTTNG_HEALTH_CHECK
;
1555 ret
= lttcomm_send_unix_sock(sock
, (void *)&msg
, sizeof(msg
));
1557 ret
= -LTTNG_ERR_FATAL
;
1561 ret
= lttcomm_recv_unix_sock(sock
, (void *)&reply
, sizeof(reply
));
1563 ret
= -LTTNG_ERR_FATAL
;
1567 ret
= reply
.ret_code
;
1577 * This is an extension of create session that is ONLY and SHOULD only be used
1578 * by the lttng command line program. It exists to avoid using URI parsing in
1581 * We need the date and time for the trace path subdirectory for the case where
1582 * the user does NOT define one using either -o or -U. Using the normal
1583 * lttng_create_session API call, we have no clue on the session daemon side if
1584 * the URL was generated automatically by the client or define by the user.
1586 * So this function "wrapper" is hidden from the public API, takes the datetime
1587 * string and appends it if necessary to the URI subdirectory before sending it
1588 * to the session daemon.
1590 * With this extra function, the lttng_create_session call behavior is not
1591 * changed and the timestamp is appended to the URI on the session daemon side
1594 int _lttng_create_session_ext(const char *name
, const char *url
,
1595 const char *datetime
)
1599 struct lttcomm_session_msg lsm
;
1600 struct lttng_uri
*uris
= NULL
;
1602 if (name
== NULL
|| datetime
== NULL
) {
1603 return -LTTNG_ERR_INVALID
;
1606 memset(&lsm
, 0, sizeof(lsm
));
1608 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1609 copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1611 /* There should never be a data URL */
1612 size
= parse_str_urls_to_uri(url
, NULL
, &uris
);
1614 return -LTTNG_ERR_INVALID
;
1617 lsm
.u
.uri
.size
= size
;
1619 if (size
> 0 && uris
[0].dtype
!= LTTNG_DST_PATH
&& strlen(uris
[0].subdir
) == 0) {
1620 ret
= snprintf(uris
[0].subdir
, sizeof(uris
[0].subdir
), "%s-%s", name
,
1623 PERROR("snprintf uri subdir");
1624 return -LTTNG_ERR_FATAL
;
1628 return ask_sessiond_varlen(&lsm
, uris
, sizeof(struct lttng_uri
) * size
,
1633 * For a given session name, this call checks if the data is ready to be read
1634 * or is still being extracted by the consumer(s) hence not ready to be used by
1637 int lttng_data_pending(const char *session_name
)
1640 struct lttcomm_session_msg lsm
;
1642 if (session_name
== NULL
) {
1643 return -LTTNG_ERR_INVALID
;
1646 lsm
.cmd_type
= LTTNG_DATA_PENDING
;
1648 copy_string(lsm
.session
.name
, session_name
, sizeof(lsm
.session
.name
));
1650 ret
= ask_sessiond(&lsm
, NULL
);
1653 * The ask_sessiond function negate the return code if it's not LTTNG_OK so
1654 * getting -1 means that the reply ret_code was 1 thus meaning that the
1655 * data is available. Yes it is hackish but for now this is the only way.
1667 static void __attribute__((constructor
)) init()
1669 /* Set default session group */
1670 lttng_set_tracing_group(DEFAULT_TRACING_GROUP
);
1671 /* Set socket for health check */
1672 (void) set_health_socket_path();
1678 static void __attribute__((destructor
)) lttng_ctl_exit()
1680 free(tracing_group
);