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
)
93 unsigned int equal
= 1, idx
= 0;
94 /* Add the "file://" size to the URL maximum size */
95 char url
[PATH_MAX
+ 7];
96 ssize_t size_ctrl
= 0, size_data
= 0, size
;
97 struct lttng_uri
*ctrl_uris
= NULL
, *data_uris
= NULL
;
98 struct lttng_uri
*tmp_uris
= NULL
;
100 /* No URL(s) is allowed. This means that the consumer will be disabled. */
101 if (ctrl_url
== NULL
&& data_url
== NULL
) {
105 /* Check if URLs are equal and if so, only use the control URL */
106 if (ctrl_url
&& data_url
) {
107 equal
= !strcmp(ctrl_url
, data_url
);
111 * Since we allow the str_url to be a full local filesystem path, we are
112 * going to create a valid file:// URL if it's the case.
114 * Check if first character is a '/' or else reject the URL.
116 if (ctrl_url
&& ctrl_url
[0] == '/') {
119 ret
= snprintf(url
, sizeof(url
), "file://%s", ctrl_url
);
121 PERROR("snprintf file url");
127 /* Parse the control URL if there is one */
129 size_ctrl
= uri_parse(ctrl_url
, &ctrl_uris
);
131 ERR("Unable to parse the URL %s", ctrl_url
);
135 /* At this point, we know there is at least one URI in the array */
136 set_default_url_attr(&ctrl_uris
[0], LTTNG_STREAM_CONTROL
);
138 if (ctrl_uris
[0].dtype
== LTTNG_DST_PATH
&& data_url
) {
139 ERR("Can not have a data URL when destination is file://");
143 /* URL are not equal but the control URL uses a net:// protocol */
144 if (size_ctrl
== 2) {
146 ERR("Control URL uses the net:// protocol and the data URL is "
147 "different. Not allowed.");
150 set_default_url_attr(&ctrl_uris
[1], LTTNG_STREAM_DATA
);
152 * The data_url and ctrl_url are equal and the ctrl_url
153 * contains a net:// protocol so we just skip the data part.
161 /* We have to parse the data URL in this case */
162 size_data
= uri_parse(data_url
, &data_uris
);
164 ERR("Unable to parse the URL %s", data_url
);
166 } else if (size_data
== 2) {
167 ERR("Data URL can not be set with the net[4|6]:// protocol");
171 set_default_url_attr(&data_uris
[0], LTTNG_STREAM_DATA
);
174 /* Compute total size */
175 size
= size_ctrl
+ size_data
;
177 tmp_uris
= zmalloc(sizeof(struct lttng_uri
) * size
);
178 if (tmp_uris
== NULL
) {
179 PERROR("zmalloc uris");
184 /* It's possible the control URIs array contains more than one URI */
185 memcpy(tmp_uris
, ctrl_uris
, sizeof(struct lttng_uri
) * size_ctrl
);
191 memcpy(&tmp_uris
[idx
], data_uris
, sizeof(struct lttng_uri
));
208 * Copy string from src to dst and enforce null terminated byte.
210 static void copy_string(char *dst
, const char *src
, size_t len
)
213 strncpy(dst
, src
, len
);
214 /* Enforce the NULL terminated byte */
222 * Copy domain to lttcomm_session_msg domain.
224 * If domain is unknown, default domain will be the kernel.
226 static void copy_lttng_domain(struct lttng_domain
*dst
, struct lttng_domain
*src
)
230 case LTTNG_DOMAIN_KERNEL
:
231 case LTTNG_DOMAIN_UST
:
233 case LTTNG_DOMAIN_UST_EXEC_NAME:
234 case LTTNG_DOMAIN_UST_PID:
235 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
237 memcpy(dst
, src
, sizeof(struct lttng_domain
));
240 memset(dst
, 0, sizeof(struct lttng_domain
));
247 * Send lttcomm_session_msg to the session daemon.
249 * On success, returns the number of bytes sent (>=0)
250 * On error, returns -1
252 static int send_session_msg(struct lttcomm_session_msg
*lsm
)
257 ret
= -LTTNG_ERR_NO_SESSIOND
;
261 DBG("LSM cmd type : %d", lsm
->cmd_type
);
263 ret
= lttcomm_send_creds_unix_sock(sessiond_socket
, lsm
,
264 sizeof(struct lttcomm_session_msg
));
266 ret
= -LTTNG_ERR_FATAL
;
274 * Send var len data to the session daemon.
276 * On success, returns the number of bytes sent (>=0)
277 * On error, returns -1
279 static int send_session_varlen(void *data
, size_t len
)
284 ret
= -LTTNG_ERR_NO_SESSIOND
;
293 ret
= lttcomm_send_unix_sock(sessiond_socket
, data
, len
);
295 ret
= -LTTNG_ERR_FATAL
;
303 * Receive data from the sessiond socket.
305 * On success, returns the number of bytes received (>=0)
306 * On error, returns -1 (recvmsg() error) or -ENOTCONN
308 static int recv_data_sessiond(void *buf
, size_t len
)
313 ret
= -LTTNG_ERR_NO_SESSIOND
;
317 ret
= lttcomm_recv_unix_sock(sessiond_socket
, buf
, len
);
319 ret
= -LTTNG_ERR_FATAL
;
327 * Check if we are in the specified group.
329 * If yes return 1, else return -1.
331 static int check_tracing_group(const char *grp_name
)
333 struct group
*grp_tracing
; /* no free(). See getgrnam(3) */
335 int grp_list_size
, grp_id
, i
;
338 /* Get GID of group 'tracing' */
339 grp_tracing
= getgrnam(grp_name
);
341 /* If grp_tracing is NULL, the group does not exist. */
345 /* Get number of supplementary group IDs */
346 grp_list_size
= getgroups(0, NULL
);
347 if (grp_list_size
< 0) {
352 /* Alloc group list of the right size */
353 grp_list
= malloc(grp_list_size
* sizeof(gid_t
));
358 grp_id
= getgroups(grp_list_size
, grp_list
);
364 for (i
= 0; i
< grp_list_size
; i
++) {
365 if (grp_list
[i
] == grp_tracing
->gr_gid
) {
379 * Try connect to session daemon with sock_path.
381 * Return 0 on success, else -1
383 static int try_connect_sessiond(const char *sock_path
)
387 /* If socket exist, we check if the daemon listens for connect. */
388 ret
= access(sock_path
, F_OK
);
394 ret
= lttcomm_connect_unix_sock(sock_path
);
400 ret
= lttcomm_close_unix_sock(ret
);
402 perror("lttcomm_close_unix_sock");
412 * Set sessiond socket path by putting it in the global sessiond_sock_path
415 * Returns 0 on success, negative value on failure (the sessiond socket path
416 * is somehow too long or ENOMEM).
418 static int set_session_daemon_path(void)
420 int in_tgroup
= 0; /* In tracing group */
426 /* Are we in the tracing group ? */
427 in_tgroup
= check_tracing_group(tracing_group
);
430 if ((uid
== 0) || in_tgroup
) {
431 copy_string(sessiond_sock_path
, DEFAULT_GLOBAL_CLIENT_UNIX_SOCK
,
432 sizeof(sessiond_sock_path
));
440 ret
= try_connect_sessiond(sessiond_sock_path
);
444 /* Global session daemon not available... */
446 /* ...or not in tracing group (and not root), default */
449 * With GNU C < 2.1, snprintf returns -1 if the target buffer is too small;
450 * With GNU C >= 2.1, snprintf returns the required size (excluding closing null)
452 ret
= snprintf(sessiond_sock_path
, sizeof(sessiond_sock_path
),
453 DEFAULT_HOME_CLIENT_UNIX_SOCK
, getenv("HOME"));
454 if ((ret
< 0) || (ret
>= sizeof(sessiond_sock_path
))) {
466 * Connect to the LTTng session daemon.
468 * On success, return 0. On error, return -1.
470 static int connect_sessiond(void)
474 ret
= set_session_daemon_path();
479 /* Connect to the sesssion daemon */
480 ret
= lttcomm_connect_unix_sock(sessiond_sock_path
);
485 sessiond_socket
= ret
;
495 * Clean disconnect from the session daemon.
496 * On success, return 0. On error, return -1.
498 static int disconnect_sessiond(void)
503 ret
= lttcomm_close_unix_sock(sessiond_socket
);
512 * Ask the session daemon a specific command and put the data into buf.
513 * Takes extra var. len. data as input to send to the session daemon.
515 * Return size of data (only payload, not header) or a negative error code.
517 static int ask_sessiond_varlen(struct lttcomm_session_msg
*lsm
,
518 void *vardata
, size_t varlen
, void **buf
)
523 struct lttcomm_lttng_msg llm
;
525 ret
= connect_sessiond();
527 ret
= -LTTNG_ERR_NO_SESSIOND
;
531 /* Send command to session daemon */
532 ret
= send_session_msg(lsm
);
534 /* Ret value is a valid lttng error code. */
537 /* Send var len data */
538 ret
= send_session_varlen(vardata
, varlen
);
540 /* Ret value is a valid lttng error code. */
544 /* Get header from data transmission */
545 ret
= recv_data_sessiond(&llm
, sizeof(llm
));
547 /* Ret value is a valid lttng error code. */
551 /* Check error code if OK */
552 if (llm
.ret_code
!= LTTNG_OK
) {
557 size
= llm
.data_size
;
559 /* If client free with size 0 */
567 data
= (void*) malloc(size
);
569 /* Get payload data */
570 ret
= recv_data_sessiond(data
, size
);
577 * Extra protection not to dereference a NULL pointer. If buf is NULL at
578 * this point, an error is returned and data is freed.
581 ret
= -LTTNG_ERR_INVALID
;
590 disconnect_sessiond();
595 * Ask the session daemon a specific command and put the data into buf.
597 * Return size of data (only payload, not header) or a negative error code.
599 static int ask_sessiond(struct lttcomm_session_msg
*lsm
, void **buf
)
601 return ask_sessiond_varlen(lsm
, NULL
, 0, buf
);
605 * Create lttng handle and return pointer.
606 * The returned pointer will be NULL in case of malloc() error.
608 struct lttng_handle
*lttng_create_handle(const char *session_name
,
609 struct lttng_domain
*domain
)
611 struct lttng_handle
*handle
= NULL
;
613 if (domain
== NULL
) {
617 handle
= malloc(sizeof(struct lttng_handle
));
618 if (handle
== NULL
) {
619 PERROR("malloc handle");
623 /* Copy session name */
624 copy_string(handle
->session_name
, session_name
,
625 sizeof(handle
->session_name
));
627 /* Copy lttng domain */
628 copy_lttng_domain(&handle
->domain
, domain
);
635 * Destroy handle by free(3) the pointer.
637 void lttng_destroy_handle(struct lttng_handle
*handle
)
643 * Register an outside consumer.
644 * Returns size of returned session payload data or a negative error code.
646 int lttng_register_consumer(struct lttng_handle
*handle
,
647 const char *socket_path
)
649 struct lttcomm_session_msg lsm
;
651 if (handle
== NULL
|| socket_path
== NULL
) {
652 return -LTTNG_ERR_INVALID
;
655 lsm
.cmd_type
= LTTNG_REGISTER_CONSUMER
;
656 copy_string(lsm
.session
.name
, handle
->session_name
,
657 sizeof(lsm
.session
.name
));
658 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
660 copy_string(lsm
.u
.reg
.path
, socket_path
, sizeof(lsm
.u
.reg
.path
));
662 return ask_sessiond(&lsm
, NULL
);
666 * Start tracing for all traces of the session.
667 * Returns size of returned session payload data or a negative error code.
669 int lttng_start_tracing(const char *session_name
)
671 struct lttcomm_session_msg lsm
;
673 if (session_name
== NULL
) {
674 return -LTTNG_ERR_INVALID
;
677 lsm
.cmd_type
= LTTNG_START_TRACE
;
679 copy_string(lsm
.session
.name
, session_name
, sizeof(lsm
.session
.name
));
681 return ask_sessiond(&lsm
, NULL
);
685 * Stop tracing for all traces of the session.
687 static int _lttng_stop_tracing(const char *session_name
, int wait
)
690 struct lttcomm_session_msg lsm
;
692 if (session_name
== NULL
) {
693 return -LTTNG_ERR_INVALID
;
696 lsm
.cmd_type
= LTTNG_STOP_TRACE
;
698 copy_string(lsm
.session
.name
, session_name
, sizeof(lsm
.session
.name
));
700 ret
= ask_sessiond(&lsm
, NULL
);
701 if (ret
< 0 && ret
!= -LTTNG_ERR_TRACE_ALREADY_STOPPED
) {
709 _MSG("Waiting for data availability");
711 /* Check for data availability */
713 data_ret
= lttng_data_pending(session_name
);
715 /* Return the data available call error. */
721 * Data sleep time before retrying (in usec). Don't sleep if the call
722 * returned value indicates availability.
725 usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME
);
728 } while (data_ret
!= 0);
738 * Stop tracing and wait for data availability.
740 int lttng_stop_tracing(const char *session_name
)
742 return _lttng_stop_tracing(session_name
, 1);
746 * Stop tracing but _don't_ wait for data availability.
748 int lttng_stop_tracing_no_wait(const char *session_name
)
750 return _lttng_stop_tracing(session_name
, 0);
754 * Add context to a channel.
756 * If the given channel is NULL, add the contexts to all channels.
757 * The event_name param is ignored.
759 * Returns the size of the returned payload data or a negative error code.
761 int lttng_add_context(struct lttng_handle
*handle
,
762 struct lttng_event_context
*ctx
, const char *event_name
,
763 const char *channel_name
)
765 struct lttcomm_session_msg lsm
;
767 /* Safety check. Both are mandatory */
768 if (handle
== NULL
|| ctx
== NULL
) {
769 return -LTTNG_ERR_INVALID
;
772 memset(&lsm
, 0, sizeof(lsm
));
774 lsm
.cmd_type
= LTTNG_ADD_CONTEXT
;
776 /* Copy channel name */
777 copy_string(lsm
.u
.context
.channel_name
, channel_name
,
778 sizeof(lsm
.u
.context
.channel_name
));
780 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
782 memcpy(&lsm
.u
.context
.ctx
, ctx
, sizeof(struct lttng_event_context
));
784 copy_string(lsm
.session
.name
, handle
->session_name
,
785 sizeof(lsm
.session
.name
));
787 return ask_sessiond(&lsm
, NULL
);
791 * Enable event(s) for a channel.
792 * If no event name is specified, all events are enabled.
793 * If no channel name is specified, the default 'channel0' is used.
794 * Returns size of returned session payload data or a negative error code.
796 int lttng_enable_event(struct lttng_handle
*handle
,
797 struct lttng_event
*ev
, const char *channel_name
)
799 struct lttcomm_session_msg lsm
;
801 if (handle
== NULL
|| ev
== NULL
) {
802 return -LTTNG_ERR_INVALID
;
805 memset(&lsm
, 0, sizeof(lsm
));
807 /* If no channel name, we put the default name */
808 if (channel_name
== NULL
) {
809 copy_string(lsm
.u
.enable
.channel_name
, DEFAULT_CHANNEL_NAME
,
810 sizeof(lsm
.u
.enable
.channel_name
));
812 copy_string(lsm
.u
.enable
.channel_name
, channel_name
,
813 sizeof(lsm
.u
.enable
.channel_name
));
816 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
818 if (ev
->name
[0] != '\0') {
819 lsm
.cmd_type
= LTTNG_ENABLE_EVENT
;
821 lsm
.cmd_type
= LTTNG_ENABLE_ALL_EVENT
;
823 memcpy(&lsm
.u
.enable
.event
, ev
, sizeof(lsm
.u
.enable
.event
));
825 copy_string(lsm
.session
.name
, handle
->session_name
,
826 sizeof(lsm
.session
.name
));
828 return ask_sessiond(&lsm
, NULL
);
832 * Create or enable an event with a filter expression.
834 * Return negative error value on error.
835 * Return size of returned session payload data if OK.
837 int lttng_enable_event_with_filter(struct lttng_handle
*handle
,
838 struct lttng_event
*event
, const char *channel_name
,
839 const char *filter_expression
)
841 struct lttcomm_session_msg lsm
;
842 struct filter_parser_ctx
*ctx
;
846 if (!filter_expression
) {
848 * Fall back to normal event enabling if no filter
851 return lttng_enable_event(handle
, event
, channel_name
);
855 * Empty filter string will always be rejected by the parser
856 * anyway, so treat this corner-case early to eliminate
857 * lttng_fmemopen error for 0-byte allocation.
859 if (handle
== NULL
|| filter_expression
[0] == '\0') {
860 return -LTTNG_ERR_INVALID
;
864 * casting const to non-const, as the underlying function will
865 * use it in read-only mode.
867 fmem
= lttng_fmemopen((void *) filter_expression
,
868 strlen(filter_expression
), "r");
870 fprintf(stderr
, "Error opening memory as stream\n");
871 return -LTTNG_ERR_FILTER_NOMEM
;
873 ctx
= filter_parser_ctx_alloc(fmem
);
875 fprintf(stderr
, "Error allocating parser\n");
876 ret
= -LTTNG_ERR_FILTER_NOMEM
;
879 ret
= filter_parser_ctx_append_ast(ctx
);
881 fprintf(stderr
, "Parse error\n");
882 ret
= -LTTNG_ERR_FILTER_INVAL
;
885 ret
= filter_visitor_set_parent(ctx
);
887 fprintf(stderr
, "Set parent error\n");
888 ret
= -LTTNG_ERR_FILTER_INVAL
;
892 ret
= filter_visitor_print_xml(ctx
, stdout
, 0);
895 fprintf(stderr
, "XML print error\n");
896 ret
= -LTTNG_ERR_FILTER_INVAL
;
901 dbg_printf("Generating IR... ");
903 ret
= filter_visitor_ir_generate(ctx
);
905 fprintf(stderr
, "Generate IR error\n");
906 ret
= -LTTNG_ERR_FILTER_INVAL
;
909 dbg_printf("done\n");
911 dbg_printf("Validating IR... ");
913 ret
= filter_visitor_ir_check_binary_op_nesting(ctx
);
915 ret
= -LTTNG_ERR_FILTER_INVAL
;
918 dbg_printf("done\n");
920 dbg_printf("Generating bytecode... ");
922 ret
= filter_visitor_bytecode_generate(ctx
);
924 fprintf(stderr
, "Generate bytecode error\n");
925 ret
= -LTTNG_ERR_FILTER_INVAL
;
928 dbg_printf("done\n");
929 dbg_printf("Size of bytecode generated: %u bytes.\n",
930 bytecode_get_len(&ctx
->bytecode
->b
));
932 memset(&lsm
, 0, sizeof(lsm
));
934 lsm
.cmd_type
= LTTNG_ENABLE_EVENT_WITH_FILTER
;
936 /* Copy channel name */
937 copy_string(lsm
.u
.enable
.channel_name
, channel_name
,
938 sizeof(lsm
.u
.enable
.channel_name
));
939 /* Copy event name */
941 memcpy(&lsm
.u
.enable
.event
, event
, sizeof(lsm
.u
.enable
.event
));
944 lsm
.u
.enable
.bytecode_len
= sizeof(ctx
->bytecode
->b
)
945 + bytecode_get_len(&ctx
->bytecode
->b
);
947 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
949 copy_string(lsm
.session
.name
, handle
->session_name
,
950 sizeof(lsm
.session
.name
));
952 ret
= ask_sessiond_varlen(&lsm
, &ctx
->bytecode
->b
,
953 lsm
.u
.enable
.bytecode_len
, NULL
);
955 filter_bytecode_free(ctx
);
957 filter_parser_ctx_free(ctx
);
958 if (fclose(fmem
) != 0) {
964 filter_bytecode_free(ctx
);
966 filter_parser_ctx_free(ctx
);
968 if (fclose(fmem
) != 0) {
975 * Disable event(s) of a channel and domain.
976 * If no event name is specified, all events are disabled.
977 * If no channel name is specified, the default 'channel0' is used.
978 * Returns size of returned session payload data or a negative error code.
980 int lttng_disable_event(struct lttng_handle
*handle
, const char *name
,
981 const char *channel_name
)
983 struct lttcomm_session_msg lsm
;
985 if (handle
== NULL
) {
986 return -LTTNG_ERR_INVALID
;
989 memset(&lsm
, 0, sizeof(lsm
));
992 copy_string(lsm
.u
.disable
.channel_name
, channel_name
,
993 sizeof(lsm
.u
.disable
.channel_name
));
995 copy_string(lsm
.u
.disable
.channel_name
, DEFAULT_CHANNEL_NAME
,
996 sizeof(lsm
.u
.disable
.channel_name
));
999 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1002 copy_string(lsm
.u
.disable
.name
, name
, sizeof(lsm
.u
.disable
.name
));
1003 lsm
.cmd_type
= LTTNG_DISABLE_EVENT
;
1005 lsm
.cmd_type
= LTTNG_DISABLE_ALL_EVENT
;
1008 copy_string(lsm
.session
.name
, handle
->session_name
,
1009 sizeof(lsm
.session
.name
));
1011 return ask_sessiond(&lsm
, NULL
);
1015 * Enable channel per domain
1016 * Returns size of returned session payload data or a negative error code.
1018 int lttng_enable_channel(struct lttng_handle
*handle
,
1019 struct lttng_channel
*chan
)
1021 struct lttcomm_session_msg lsm
;
1024 * NULL arguments are forbidden. No default values.
1026 if (handle
== NULL
|| chan
== NULL
) {
1027 return -LTTNG_ERR_INVALID
;
1030 memset(&lsm
, 0, sizeof(lsm
));
1032 memcpy(&lsm
.u
.channel
.chan
, chan
, sizeof(lsm
.u
.channel
.chan
));
1034 lsm
.cmd_type
= LTTNG_ENABLE_CHANNEL
;
1036 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1038 copy_string(lsm
.session
.name
, handle
->session_name
,
1039 sizeof(lsm
.session
.name
));
1041 return ask_sessiond(&lsm
, NULL
);
1045 * All tracing will be stopped for registered events of the channel.
1046 * Returns size of returned session payload data or a negative error code.
1048 int lttng_disable_channel(struct lttng_handle
*handle
, const char *name
)
1050 struct lttcomm_session_msg lsm
;
1052 /* Safety check. Both are mandatory */
1053 if (handle
== NULL
|| name
== NULL
) {
1054 return -LTTNG_ERR_INVALID
;
1057 memset(&lsm
, 0, sizeof(lsm
));
1059 lsm
.cmd_type
= LTTNG_DISABLE_CHANNEL
;
1061 copy_string(lsm
.u
.disable
.channel_name
, name
,
1062 sizeof(lsm
.u
.disable
.channel_name
));
1064 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1066 copy_string(lsm
.session
.name
, handle
->session_name
,
1067 sizeof(lsm
.session
.name
));
1069 return ask_sessiond(&lsm
, NULL
);
1073 * Lists all available tracepoints of domain.
1074 * Sets the contents of the events array.
1075 * Returns the number of lttng_event entries in events;
1076 * on error, returns a negative value.
1078 int lttng_list_tracepoints(struct lttng_handle
*handle
,
1079 struct lttng_event
**events
)
1082 struct lttcomm_session_msg lsm
;
1084 if (handle
== NULL
) {
1085 return -LTTNG_ERR_INVALID
;
1088 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINTS
;
1089 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1091 ret
= ask_sessiond(&lsm
, (void **) events
);
1096 return ret
/ sizeof(struct lttng_event
);
1100 * Lists all available tracepoint fields of domain.
1101 * Sets the contents of the event field array.
1102 * Returns the number of lttng_event_field entries in events;
1103 * on error, returns a negative value.
1105 int lttng_list_tracepoint_fields(struct lttng_handle
*handle
,
1106 struct lttng_event_field
**fields
)
1109 struct lttcomm_session_msg lsm
;
1111 if (handle
== NULL
) {
1112 return -LTTNG_ERR_INVALID
;
1115 lsm
.cmd_type
= LTTNG_LIST_TRACEPOINT_FIELDS
;
1116 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1118 ret
= ask_sessiond(&lsm
, (void **) fields
);
1123 return ret
/ sizeof(struct lttng_event_field
);
1127 * Returns a human readable string describing
1128 * the error code (a negative value).
1130 const char *lttng_strerror(int code
)
1132 return error_get_str(code
);
1136 * Create a brand new session using name and url for destination.
1138 * Returns LTTNG_OK on success or a negative error code.
1140 int lttng_create_session(const char *name
, const char *url
)
1144 struct lttcomm_session_msg lsm
;
1145 struct lttng_uri
*uris
= NULL
;
1148 return -LTTNG_ERR_INVALID
;
1151 memset(&lsm
, 0, sizeof(lsm
));
1153 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1154 copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1156 /* There should never be a data URL */
1157 size
= parse_str_urls_to_uri(url
, NULL
, &uris
);
1159 return -LTTNG_ERR_INVALID
;
1162 lsm
.u
.uri
.size
= size
;
1164 ret
= ask_sessiond_varlen(&lsm
, uris
, sizeof(struct lttng_uri
) * size
,
1172 * Destroy session using name.
1173 * Returns size of returned session payload data or a negative error code.
1175 int lttng_destroy_session(const char *session_name
)
1177 struct lttcomm_session_msg lsm
;
1179 if (session_name
== NULL
) {
1180 return -LTTNG_ERR_INVALID
;
1183 lsm
.cmd_type
= LTTNG_DESTROY_SESSION
;
1185 copy_string(lsm
.session
.name
, session_name
, sizeof(lsm
.session
.name
));
1187 return ask_sessiond(&lsm
, NULL
);
1191 * Ask the session daemon for all available sessions.
1192 * Sets the contents of the sessions array.
1193 * Returns the number of lttng_session entries in sessions;
1194 * on error, returns a negative value.
1196 int lttng_list_sessions(struct lttng_session
**sessions
)
1199 struct lttcomm_session_msg lsm
;
1201 lsm
.cmd_type
= LTTNG_LIST_SESSIONS
;
1202 ret
= ask_sessiond(&lsm
, (void**) sessions
);
1207 return ret
/ sizeof(struct lttng_session
);
1211 * Ask the session daemon for all available domains of a session.
1212 * Sets the contents of the domains array.
1213 * Returns the number of lttng_domain entries in domains;
1214 * on error, returns a negative value.
1216 int lttng_list_domains(const char *session_name
,
1217 struct lttng_domain
**domains
)
1220 struct lttcomm_session_msg lsm
;
1222 if (session_name
== NULL
) {
1223 return -LTTNG_ERR_INVALID
;
1226 lsm
.cmd_type
= LTTNG_LIST_DOMAINS
;
1228 copy_string(lsm
.session
.name
, session_name
, sizeof(lsm
.session
.name
));
1230 ret
= ask_sessiond(&lsm
, (void**) domains
);
1235 return ret
/ sizeof(struct lttng_domain
);
1239 * Ask the session daemon for all available channels of a session.
1240 * Sets the contents of the channels array.
1241 * Returns the number of lttng_channel entries in channels;
1242 * on error, returns a negative value.
1244 int lttng_list_channels(struct lttng_handle
*handle
,
1245 struct lttng_channel
**channels
)
1248 struct lttcomm_session_msg lsm
;
1250 if (handle
== NULL
) {
1251 return -LTTNG_ERR_INVALID
;
1254 lsm
.cmd_type
= LTTNG_LIST_CHANNELS
;
1255 copy_string(lsm
.session
.name
, handle
->session_name
,
1256 sizeof(lsm
.session
.name
));
1258 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1260 ret
= ask_sessiond(&lsm
, (void**) channels
);
1265 return ret
/ sizeof(struct lttng_channel
);
1269 * Ask the session daemon for all available events of a session channel.
1270 * Sets the contents of the events array.
1271 * Returns the number of lttng_event entries in events;
1272 * on error, returns a negative value.
1274 int lttng_list_events(struct lttng_handle
*handle
,
1275 const char *channel_name
, struct lttng_event
**events
)
1278 struct lttcomm_session_msg lsm
;
1280 /* Safety check. An handle and channel name are mandatory */
1281 if (handle
== NULL
|| channel_name
== NULL
) {
1282 return -LTTNG_ERR_INVALID
;
1285 lsm
.cmd_type
= LTTNG_LIST_EVENTS
;
1286 copy_string(lsm
.session
.name
, handle
->session_name
,
1287 sizeof(lsm
.session
.name
));
1288 copy_string(lsm
.u
.list
.channel_name
, channel_name
,
1289 sizeof(lsm
.u
.list
.channel_name
));
1291 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1293 ret
= ask_sessiond(&lsm
, (void**) events
);
1298 return ret
/ sizeof(struct lttng_event
);
1302 * Sets the tracing_group variable with name.
1303 * This function allocates memory pointed to by tracing_group.
1304 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
1306 int lttng_set_tracing_group(const char *name
)
1309 return -LTTNG_ERR_INVALID
;
1312 if (asprintf(&tracing_group
, "%s", name
) < 0) {
1313 return -LTTNG_ERR_FATAL
;
1320 * Returns size of returned session payload data or a negative error code.
1322 int lttng_calibrate(struct lttng_handle
*handle
,
1323 struct lttng_calibrate
*calibrate
)
1325 struct lttcomm_session_msg lsm
;
1327 /* Safety check. NULL pointer are forbidden */
1328 if (handle
== NULL
|| calibrate
== NULL
) {
1329 return -LTTNG_ERR_INVALID
;
1332 lsm
.cmd_type
= LTTNG_CALIBRATE
;
1333 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1335 memcpy(&lsm
.u
.calibrate
, calibrate
, sizeof(lsm
.u
.calibrate
));
1337 return ask_sessiond(&lsm
, NULL
);
1341 * Set default channel attributes.
1342 * If either or both of the arguments are null, attr content is zeroe'd.
1344 void lttng_channel_set_default_attr(struct lttng_domain
*domain
,
1345 struct lttng_channel_attr
*attr
)
1348 if (attr
== NULL
|| domain
== NULL
) {
1352 memset(attr
, 0, sizeof(struct lttng_channel_attr
));
1354 switch (domain
->type
) {
1355 case LTTNG_DOMAIN_KERNEL
:
1356 attr
->overwrite
= DEFAULT_CHANNEL_OVERWRITE
;
1357 attr
->switch_timer_interval
= DEFAULT_CHANNEL_SWITCH_TIMER
;
1358 attr
->read_timer_interval
= DEFAULT_CHANNEL_READ_TIMER
;
1360 attr
->subbuf_size
= default_get_kernel_channel_subbuf_size();
1361 attr
->num_subbuf
= DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM
;
1362 attr
->output
= DEFAULT_KERNEL_CHANNEL_OUTPUT
;
1364 case LTTNG_DOMAIN_UST
:
1366 case LTTNG_DOMAIN_UST_EXEC_NAME
:
1367 case LTTNG_DOMAIN_UST_PID
:
1368 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN
:
1370 attr
->overwrite
= DEFAULT_CHANNEL_OVERWRITE
;
1371 attr
->switch_timer_interval
= DEFAULT_CHANNEL_SWITCH_TIMER
;
1372 attr
->read_timer_interval
= DEFAULT_CHANNEL_READ_TIMER
;
1374 attr
->subbuf_size
= default_get_ust_channel_subbuf_size();
1375 attr
->num_subbuf
= DEFAULT_UST_CHANNEL_SUBBUF_NUM
;
1376 attr
->output
= DEFAULT_UST_CHANNEL_OUTPUT
;
1379 /* Default behavior: leave set to 0. */
1385 * Check if session daemon is alive.
1387 * Return 1 if alive or 0 if not.
1388 * On error returns a negative value.
1390 int lttng_session_daemon_alive(void)
1394 ret
= set_session_daemon_path();
1400 if (*sessiond_sock_path
== '\0') {
1402 * No socket path set. Weird error which means the constructor was not
1408 ret
= try_connect_sessiond(sessiond_sock_path
);
1419 * Set URL for a consumer for a session and domain.
1421 * Return 0 on success, else a negative value.
1423 int lttng_set_consumer_url(struct lttng_handle
*handle
,
1424 const char *control_url
, const char *data_url
)
1428 struct lttcomm_session_msg lsm
;
1429 struct lttng_uri
*uris
= NULL
;
1431 if (handle
== NULL
|| (control_url
== NULL
&& data_url
== NULL
)) {
1432 return -LTTNG_ERR_INVALID
;
1435 memset(&lsm
, 0, sizeof(lsm
));
1437 lsm
.cmd_type
= LTTNG_SET_CONSUMER_URI
;
1439 copy_string(lsm
.session
.name
, handle
->session_name
,
1440 sizeof(lsm
.session
.name
));
1441 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1443 size
= parse_str_urls_to_uri(control_url
, data_url
, &uris
);
1445 return -LTTNG_ERR_INVALID
;
1448 lsm
.u
.uri
.size
= size
;
1450 ret
= ask_sessiond_varlen(&lsm
, uris
, sizeof(struct lttng_uri
) * size
,
1458 * Enable consumer for a session and domain.
1460 * Return 0 on success, else a negative value.
1462 int lttng_enable_consumer(struct lttng_handle
*handle
)
1464 struct lttcomm_session_msg lsm
;
1466 if (handle
== NULL
) {
1467 return -LTTNG_ERR_INVALID
;
1470 lsm
.cmd_type
= LTTNG_ENABLE_CONSUMER
;
1472 copy_string(lsm
.session
.name
, handle
->session_name
,
1473 sizeof(lsm
.session
.name
));
1474 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1476 return ask_sessiond(&lsm
, NULL
);
1480 * Disable consumer for a session and domain.
1482 * Return 0 on success, else a negative value.
1484 int lttng_disable_consumer(struct lttng_handle
*handle
)
1486 struct lttcomm_session_msg lsm
;
1488 if (handle
== NULL
) {
1489 return -LTTNG_ERR_INVALID
;
1492 lsm
.cmd_type
= LTTNG_DISABLE_CONSUMER
;
1494 copy_string(lsm
.session
.name
, handle
->session_name
,
1495 sizeof(lsm
.session
.name
));
1496 copy_lttng_domain(&lsm
.domain
, &handle
->domain
);
1498 return ask_sessiond(&lsm
, NULL
);
1502 * Set health socket path by putting it in the global health_sock_path
1505 * Returns 0 on success or assert(0) on ENOMEM.
1507 static int set_health_socket_path(void)
1509 int in_tgroup
= 0; /* In tracing group */
1516 /* Are we in the tracing group ? */
1517 in_tgroup
= check_tracing_group(tracing_group
);
1520 if ((uid
== 0) || in_tgroup
) {
1521 copy_string(health_sock_path
, DEFAULT_GLOBAL_HEALTH_UNIX_SOCK
,
1522 sizeof(health_sock_path
));
1529 * With GNU C < 2.1, snprintf returns -1 if the target buffer is too small;
1530 * With GNU C >= 2.1, snprintf returns the required size (excluding closing null)
1532 home
= getenv("HOME");
1534 /* Fallback in /tmp .. */
1538 ret
= snprintf(health_sock_path
, sizeof(health_sock_path
),
1539 DEFAULT_HOME_HEALTH_UNIX_SOCK
, home
);
1540 if ((ret
< 0) || (ret
>= sizeof(health_sock_path
))) {
1541 /* ENOMEM at this point... just kill the control lib. */
1550 * Check session daemon health for a specific health component.
1552 * Return 0 if health is OK or else 1 if BAD.
1554 * Any other negative value is a lttng error code which can be translated with
1557 int lttng_health_check(enum lttng_health_component c
)
1560 struct lttcomm_health_msg msg
;
1561 struct lttcomm_health_data reply
;
1563 /* Connect to the sesssion daemon */
1564 sock
= lttcomm_connect_unix_sock(health_sock_path
);
1566 ret
= -LTTNG_ERR_NO_SESSIOND
;
1570 msg
.cmd
= LTTNG_HEALTH_CHECK
;
1573 ret
= lttcomm_send_unix_sock(sock
, (void *)&msg
, sizeof(msg
));
1575 ret
= -LTTNG_ERR_FATAL
;
1579 ret
= lttcomm_recv_unix_sock(sock
, (void *)&reply
, sizeof(reply
));
1581 ret
= -LTTNG_ERR_FATAL
;
1585 ret
= reply
.ret_code
;
1595 * This is an extension of create session that is ONLY and SHOULD only be used
1596 * by the lttng command line program. It exists to avoid using URI parsing in
1599 * We need the date and time for the trace path subdirectory for the case where
1600 * the user does NOT define one using either -o or -U. Using the normal
1601 * lttng_create_session API call, we have no clue on the session daemon side if
1602 * the URL was generated automatically by the client or define by the user.
1604 * So this function "wrapper" is hidden from the public API, takes the datetime
1605 * string and appends it if necessary to the URI subdirectory before sending it
1606 * to the session daemon.
1608 * With this extra function, the lttng_create_session call behavior is not
1609 * changed and the timestamp is appended to the URI on the session daemon side
1612 int _lttng_create_session_ext(const char *name
, const char *url
,
1613 const char *datetime
)
1617 struct lttcomm_session_msg lsm
;
1618 struct lttng_uri
*uris
= NULL
;
1620 if (name
== NULL
|| datetime
== NULL
) {
1621 return -LTTNG_ERR_INVALID
;
1624 memset(&lsm
, 0, sizeof(lsm
));
1626 lsm
.cmd_type
= LTTNG_CREATE_SESSION
;
1627 copy_string(lsm
.session
.name
, name
, sizeof(lsm
.session
.name
));
1629 /* There should never be a data URL */
1630 size
= parse_str_urls_to_uri(url
, NULL
, &uris
);
1632 ret
= -LTTNG_ERR_INVALID
;
1636 lsm
.u
.uri
.size
= size
;
1638 if (size
> 0 && uris
[0].dtype
!= LTTNG_DST_PATH
&& strlen(uris
[0].subdir
) == 0) {
1639 ret
= snprintf(uris
[0].subdir
, sizeof(uris
[0].subdir
), "%s-%s", name
,
1642 PERROR("snprintf uri subdir");
1643 ret
= -LTTNG_ERR_FATAL
;
1648 ret
= ask_sessiond_varlen(&lsm
, uris
, sizeof(struct lttng_uri
) * size
,
1657 * For a given session name, this call checks if the data is ready to be read
1658 * or is still being extracted by the consumer(s) hence not ready to be used by
1661 int lttng_data_pending(const char *session_name
)
1664 struct lttcomm_session_msg lsm
;
1666 if (session_name
== NULL
) {
1667 return -LTTNG_ERR_INVALID
;
1670 lsm
.cmd_type
= LTTNG_DATA_PENDING
;
1672 copy_string(lsm
.session
.name
, session_name
, sizeof(lsm
.session
.name
));
1674 ret
= ask_sessiond(&lsm
, NULL
);
1677 * The ask_sessiond function negate the return code if it's not LTTNG_OK so
1678 * getting -1 means that the reply ret_code was 1 thus meaning that the
1679 * data is available. Yes it is hackish but for now this is the only way.
1691 static void __attribute__((constructor
)) init()
1693 /* Set default session group */
1694 lttng_set_tracing_group(DEFAULT_TRACING_GROUP
);
1695 /* Set socket for health check */
1696 (void) set_health_socket_path();
1702 static void __attribute__((destructor
)) lttng_ctl_exit()
1704 free(tracing_group
);