2 * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version 2
7 * of the License, or (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
27 #include <lttng/lttng.h>
29 #include "liblttsessiondcomm.h"
31 #include "lttng-share.h"
33 /* Socket to session daemon for communication */
34 static int sessiond_socket
;
35 static char sessiond_sock_path
[PATH_MAX
];
37 /* Communication structure to ltt-sessiond */
38 static struct lttcomm_session_msg lsm
;
39 static struct lttcomm_lttng_msg llm
;
42 static char *tracing_group
;
48 * Send lttcomm_session_msg to the session daemon.
50 * On success, return 0
51 * On error, return error code
53 static int send_data_sessiond(void)
62 ret
= lttcomm_send_unix_sock(sessiond_socket
, &lsm
, sizeof(lsm
));
71 * Receive data from the sessiond socket.
73 * On success, return 0
74 * On error, return recv() error code
76 static int recv_data_sessiond(void *buf
, size_t len
)
85 ret
= lttcomm_recv_unix_sock(sessiond_socket
, buf
, len
);
92 * Check if the specified group name exist.
94 * If yes return 0, else return -1.
96 static int check_tracing_group(const char *grp_name
)
98 struct group
*grp_tracing
; /* no free(). See getgrnam(3) */
100 int grp_list_size
, grp_id
, i
;
103 /* Get GID of group 'tracing' */
104 grp_tracing
= getgrnam(grp_name
);
105 if (grp_tracing
== NULL
) {
106 /* NULL means not found also. getgrnam(3) */
113 /* Get number of supplementary group IDs */
114 grp_list_size
= getgroups(0, NULL
);
115 if (grp_list_size
< 0) {
120 /* Alloc group list of the right size */
121 grp_list
= malloc(grp_list_size
* sizeof(gid_t
));
122 grp_id
= getgroups(grp_list_size
, grp_list
);
128 for (i
= 0; i
< grp_list_size
; i
++) {
129 if (grp_list
[i
] == grp_tracing
->gr_gid
) {
143 * Set sessiond socket path by putting it in the global sessiond_sock_path
146 static int set_session_daemon_path(void)
150 /* Are we in the tracing group ? */
151 ret
= check_tracing_group(tracing_group
);
152 if (ret
< 0 && getuid() != 0) {
153 if (sprintf(sessiond_sock_path
, DEFAULT_HOME_CLIENT_UNIX_SOCK
,
154 getenv("HOME")) < 0) {
158 strncpy(sessiond_sock_path
, DEFAULT_GLOBAL_CLIENT_UNIX_SOCK
,
159 sizeof(DEFAULT_GLOBAL_CLIENT_UNIX_SOCK
));
166 * Connect to the LTTng session daemon.
168 * On success, return 0. On error, return -1.
170 static int connect_sessiond(void)
174 ret
= set_session_daemon_path();
179 /* Connect to the sesssion daemon */
180 ret
= lttcomm_connect_unix_sock(sessiond_sock_path
);
185 sessiond_socket
= ret
;
192 * Clean disconnect the session daemon.
194 static int disconnect_sessiond(void)
199 ret
= lttcomm_close_unix_sock(sessiond_socket
);
210 * Ask the session daemon a specific command and put the data into buf.
212 * Return size of data (only payload, not header).
214 static int ask_sessiond(enum lttcomm_sessiond_command lct
, void **buf
)
220 ret
= connect_sessiond();
227 /* Send command to session daemon */
228 ret
= send_data_sessiond();
233 /* Get header from data transmission */
234 ret
= recv_data_sessiond(&llm
, sizeof(llm
));
239 /* Check error code if OK */
240 if (llm
.ret_code
!= LTTCOMM_OK
) {
245 size
= llm
.data_size
;
251 data
= (void*) malloc(size
);
253 /* Get payload data */
254 ret
= recv_data_sessiond(data
, size
);
264 disconnect_sessiond();
269 * Start tracing for all trace of the session.
271 int lttng_start_tracing(const char *session_name
)
273 strncpy(lsm
.session_name
, session_name
, NAME_MAX
);
274 return ask_sessiond(LTTNG_START_TRACE
, NULL
);
278 * Stop tracing for all trace of the session.
280 int lttng_stop_tracing(const char *session_name
)
282 strncpy(lsm
.session_name
, session_name
, NAME_MAX
);
283 return ask_sessiond(LTTNG_STOP_TRACE
, NULL
);
289 int lttng_add_context(struct lttng_domain
*domain
,
290 struct lttng_event_context
*ctx
, const char *event_name
,
291 const char *channel_name
)
295 if (channel_name
!= NULL
) {
296 strncpy(lsm
.u
.context
.channel_name
, channel_name
, NAME_MAX
);
299 if (event_name
!= NULL
) {
300 strncpy(lsm
.u
.context
.event_name
, event_name
, NAME_MAX
);
303 memcpy(&lsm
.u
.context
.ctx
, ctx
, sizeof(struct lttng_event_context
));
305 switch (domain
->type
) {
306 case LTTNG_DOMAIN_KERNEL
:
307 ret
= ask_sessiond(LTTNG_KERNEL_ADD_CONTEXT
, NULL
);
309 case LTTNG_DOMAIN_UST
:
310 ret
= LTTCOMM_NOT_IMPLEMENTED
;
313 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
323 int lttng_enable_event(struct lttng_domain
*domain
,
324 struct lttng_event
*ev
, const char *channel_name
)
328 if (channel_name
== NULL
) {
329 strncpy(lsm
.u
.enable
.channel_name
, DEFAULT_CHANNEL_NAME
, NAME_MAX
);
331 strncpy(lsm
.u
.enable
.channel_name
, channel_name
, NAME_MAX
);
334 switch (domain
->type
) {
335 case LTTNG_DOMAIN_KERNEL
:
337 ret
= ask_sessiond(LTTNG_KERNEL_ENABLE_ALL_EVENT
, NULL
);
339 memcpy(&lsm
.u
.enable
.event
, ev
, sizeof(struct lttng_event
));
340 ret
= ask_sessiond(LTTNG_KERNEL_ENABLE_EVENT
, NULL
);
343 case LTTNG_DOMAIN_UST
:
344 ret
= LTTCOMM_NOT_IMPLEMENTED
;
347 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
355 * Disable an event in the kernel tracer.
357 int lttng_disable_event(struct lttng_domain
*domain
, const char *name
,
358 const char *channel_name
)
362 if (channel_name
== NULL
) {
363 strncpy(lsm
.u
.disable
.channel_name
, DEFAULT_CHANNEL_NAME
, NAME_MAX
);
365 strncpy(lsm
.u
.disable
.channel_name
, channel_name
, NAME_MAX
);
368 switch (domain
->type
) {
369 case LTTNG_DOMAIN_KERNEL
:
371 ret
= ask_sessiond(LTTNG_KERNEL_DISABLE_ALL_EVENT
, NULL
);
373 strncpy(lsm
.u
.disable
.name
, name
, NAME_MAX
);
374 ret
= ask_sessiond(LTTNG_KERNEL_DISABLE_EVENT
, NULL
);
377 case LTTNG_DOMAIN_UST
:
378 ret
= LTTCOMM_NOT_IMPLEMENTED
;
381 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
389 * Enable recording for a channel for the kernel tracer.
391 int lttng_enable_channel(struct lttng_domain
*domain
,
392 struct lttng_channel
*chan
)
396 memcpy(&lsm
.u
.channel
.chan
, chan
, sizeof(struct lttng_channel
));
398 switch (domain
->type
) {
399 case LTTNG_DOMAIN_KERNEL
:
400 ret
= ask_sessiond(LTTNG_KERNEL_ENABLE_CHANNEL
, NULL
);
402 case LTTNG_DOMAIN_UST
:
403 ret
= LTTCOMM_NOT_IMPLEMENTED
;
406 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
414 * Disable recording for the channel for the kernel tracer.
416 int lttng_disable_channel(struct lttng_domain
*domain
, const char *name
)
420 strncpy(lsm
.u
.disable
.channel_name
, name
, NAME_MAX
);
422 switch (domain
->type
) {
423 case LTTNG_DOMAIN_KERNEL
:
424 ret
= ask_sessiond(LTTNG_KERNEL_DISABLE_CHANNEL
, NULL
);
426 case LTTNG_DOMAIN_UST
:
427 ret
= LTTCOMM_NOT_IMPLEMENTED
;
430 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
438 * List all available events in the kernel.
440 * Return the size (bytes) of the list and set the event_list array.
441 * On error, return negative value.
443 int lttng_list_events(struct lttng_domain
*domain
, char **event_list
)
447 switch (domain
->type
) {
448 case LTTNG_DOMAIN_KERNEL
:
449 ret
= ask_sessiond(LTTNG_KERNEL_LIST_EVENTS
, (void **) event_list
);
451 case LTTNG_DOMAIN_UST
:
452 ret
= LTTCOMM_NOT_IMPLEMENTED
;
455 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
463 * Return a human readable string of code
465 const char *lttng_get_readable_code(int code
)
467 if (code
> -LTTCOMM_OK
) {
468 return "Ended with errors";
471 return lttcomm_get_readable_code(code
);
475 * Create a brand new session using name.
477 int lttng_create_session(const char *name
, const char *path
)
479 strncpy(lsm
.session_name
, name
, NAME_MAX
);
480 strncpy(lsm
.path
, path
, PATH_MAX
);
481 return ask_sessiond(LTTNG_CREATE_SESSION
, NULL
);
485 * Destroy session using name.
487 int lttng_destroy_session(const char *name
)
489 strncpy(lsm
.session_name
, name
, NAME_MAX
);
490 return ask_sessiond(LTTNG_DESTROY_SESSION
, NULL
);
494 * Ask the session daemon for all available sessions.
496 * Return number of session.
497 * On error, return negative value.
499 int lttng_list_sessions(struct lttng_session
**sessions
)
503 ret
= ask_sessiond(LTTNG_LIST_SESSIONS
, (void**) sessions
);
508 return ret
/ sizeof(struct lttng_session
);
512 * Set session name for the current lsm.
514 void lttng_set_session_name(const char *name
)
516 strncpy(lsm
.session_name
, name
, NAME_MAX
);
520 * lttng_set_tracing_group
522 * Set tracing group variable with name. This function
523 * allocate memory pointed by tracing_group.
525 int lttng_set_tracing_group(const char *name
)
527 if (asprintf(&tracing_group
, "%s", name
) < 0) {
535 * lttng_check_session_daemon
539 * Error, return negative value
541 int lttng_session_daemon_alive(void)
545 ret
= set_session_daemon_path();
551 /* If socket exist, we consider the daemon started */
552 ret
= access(sessiond_sock_path
, F_OK
);
565 static void __attribute__((constructor
)) init()
567 /* Set default session group */
568 lttng_set_tracing_group(LTTNG_DEFAULT_TRACING_GROUP
);