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.
25 #include <semaphore.h>
32 #include <sys/socket.h>
34 #include <sys/types.h>
37 #include <urcu/list.h> /* URCU list library (-lurcu) */
38 #include <ust/ustctl.h> /* UST control lib (-lust) */
39 #include <lttng/lttng.h>
41 #include "liblttsessiondcomm.h"
42 #include "ltt-sessiond.h"
44 #include "kernel-ctl.h"
47 #include "traceable-app.h"
48 #include "lttng-kconsumerd.h"
52 * teardown: signal SIGTERM handler -> write into pipe. Threads waits
53 * with epoll on pipe and on other pipes/sockets for commands. Main
54 * simply waits on pthread join.
58 const char default_home_dir
[] = DEFAULT_HOME_DIR
;
59 const char default_tracing_group
[] = LTTNG_DEFAULT_TRACING_GROUP
;
60 const char default_ust_sock_dir
[] = DEFAULT_UST_SOCK_DIR
;
61 const char default_global_apps_pipe
[] = DEFAULT_GLOBAL_APPS_PIPE
;
64 int opt_verbose
; /* Not static for lttngerr.h */
65 int opt_quiet
; /* Not static for lttngerr.h */
67 const char *opt_tracing_group
;
68 static int opt_sig_parent
;
69 static int opt_daemon
;
70 static int is_root
; /* Set to 1 if the daemon is running as root */
71 static pid_t ppid
; /* Parent PID for --sig-parent option */
72 static pid_t kconsumerd_pid
;
74 static char apps_unix_sock_path
[PATH_MAX
]; /* Global application Unix socket path */
75 static char client_unix_sock_path
[PATH_MAX
]; /* Global client Unix socket path */
76 static char kconsumerd_err_unix_sock_path
[PATH_MAX
]; /* kconsumerd error Unix socket path */
77 static char kconsumerd_cmd_unix_sock_path
[PATH_MAX
]; /* kconsumerd command Unix socket path */
80 static int client_sock
;
82 static int kconsumerd_err_sock
;
83 static int kconsumerd_cmd_sock
;
84 static int kernel_tracer_fd
;
86 /* Pthread, Mutexes and Semaphores */
87 static pthread_t kconsumerd_thread
;
88 static pthread_t apps_thread
;
89 static pthread_t client_thread
;
90 static sem_t kconsumerd_sem
;
92 static pthread_mutex_t kconsumerd_pid_mutex
; /* Mutex to control kconsumerd pid assignation */
95 * teardown_kernel_session
97 * Complete teardown of a kernel session. This free all data structure
98 * related to a kernel session and update counter.
100 static void teardown_kernel_session(struct ltt_session
*session
)
102 if (session
->kernel_session
!= NULL
) {
103 DBG("Tearing down kernel session");
104 trace_destroy_kernel_session(session
->kernel_session
);
105 /* Extra precaution */
106 session
->kernel_session
= NULL
;
107 /* Decrement session count */
108 session
->kern_session_count
--;
115 * Cleanup the daemon on exit
117 static void cleanup()
121 struct ltt_session
*sess
;
126 MSG("\n%c[%d;%dm*** assert failed *** ==> %c[%dm", 27,1,31,27,0);
127 MSG("%c[%d;%dmMatthew, BEET driven development works!%c[%dm",27,1,33,27,0);
130 /* Stopping all threads */
131 DBG("Terminating all threads");
132 pthread_cancel(client_thread
);
133 pthread_cancel(apps_thread
);
134 if (kconsumerd_pid
!= 0) {
135 pthread_cancel(kconsumerd_thread
);
138 DBG("Unlinking all unix socket");
139 unlink(client_unix_sock_path
);
140 unlink(apps_unix_sock_path
);
141 unlink(kconsumerd_err_unix_sock_path
);
143 DBG("Removing %s directory", LTTNG_RUNDIR
);
144 ret
= asprintf(&cmd
, "rm -rf " LTTNG_RUNDIR
);
146 ERR("asprintf failed. Something is really wrong!");
149 /* Remove lttng run directory */
152 ERR("Unable to clean " LTTNG_RUNDIR
);
155 DBG("Cleaning up all session");
156 /* Cleanup ALL session */
157 cds_list_for_each_entry(sess
, <t_session_list
.head
, list
) {
158 teardown_kernel_session(sess
);
159 // TODO complete session cleanup (including UST)
162 close(kernel_tracer_fd
);
168 * Send data on a unix socket using the liblttsessiondcomm API.
170 * Return lttcomm error code.
172 static int send_unix_sock(int sock
, void *buf
, size_t len
)
174 /* Check valid length */
179 return lttcomm_send_unix_sock(sock
, buf
, len
);
185 * Free memory of a command context structure.
187 static void clean_command_ctx(struct command_ctx
*cmd_ctx
)
189 DBG("Clean command context structure %p", cmd_ctx
);
205 * Return a socket connected to the libust communication socket
206 * of the application identified by the pid.
208 * If the pid is not found in the traceable list,
209 * return -1 to indicate error.
211 static int ust_connect_app(pid_t pid
)
214 struct ltt_traceable_app
*lta
;
216 DBG("Connect to application pid %d", pid
);
218 lta
= find_app_by_pid(pid
);
221 DBG("Application pid %d not found", pid
);
225 sock
= ustctl_connect_pid(lta
->pid
);
227 ERR("Fail connecting to the PID %d\n", pid
);
236 * Notify apps by writing 42 to a named pipe using name.
237 * Every applications waiting for a ltt-sessiond will be notified
238 * and re-register automatically to the session daemon.
240 * Return open or write error value.
242 static int notify_apps(const char *name
)
247 DBG("Notify the global application pipe");
249 /* Try opening the global pipe */
250 fd
= open(name
, O_WRONLY
);
255 /* Notify by writing on the pipe */
256 ret
= write(fd
, "42", 2);
268 * Setup the outgoing data buffer for the response (llm) by allocating the
269 * right amount of memory and copying the original information from the lsm
272 * Return total size of the buffer pointed by buf.
274 static int setup_lttng_msg(struct command_ctx
*cmd_ctx
, size_t size
)
276 int ret
, buf_size
, trace_name_size
;
279 * Check for the trace_name. If defined, it's part of the payload data of
282 trace_name_size
= strlen(cmd_ctx
->lsm
->trace_name
);
283 buf_size
= trace_name_size
+ size
;
285 cmd_ctx
->llm
= malloc(sizeof(struct lttcomm_lttng_msg
) + buf_size
);
286 if (cmd_ctx
->llm
== NULL
) {
292 /* Copy common data */
293 cmd_ctx
->llm
->cmd_type
= cmd_ctx
->lsm
->cmd_type
;
294 cmd_ctx
->llm
->pid
= cmd_ctx
->lsm
->pid
;
295 if (!uuid_is_null(cmd_ctx
->lsm
->session_uuid
)) {
296 uuid_copy(cmd_ctx
->llm
->session_uuid
, cmd_ctx
->lsm
->session_uuid
);
299 cmd_ctx
->llm
->trace_name_offset
= trace_name_size
;
300 cmd_ctx
->llm
->data_size
= size
;
301 cmd_ctx
->lttng_msg_size
= sizeof(struct lttcomm_lttng_msg
) + buf_size
;
303 /* Copy trace name to the llm structure. Begining of the payload. */
304 memcpy(cmd_ctx
->llm
->payload
, cmd_ctx
->lsm
->trace_name
, trace_name_size
);
313 * thread_manage_kconsumerd
315 * This thread manage the kconsumerd error sent
316 * back to the session daemon.
318 static void *thread_manage_kconsumerd(void *data
)
321 enum lttcomm_return_code code
;
323 DBG("[thread] Manage kconsumerd started");
325 ret
= lttcomm_listen_unix_sock(kconsumerd_err_sock
);
330 sock
= lttcomm_accept_unix_sock(kconsumerd_err_sock
);
335 /* Getting status code from kconsumerd */
336 ret
= lttcomm_recv_unix_sock(sock
, &code
, sizeof(enum lttcomm_return_code
));
341 if (code
== KCONSUMERD_COMMAND_SOCK_READY
) {
342 kconsumerd_cmd_sock
= lttcomm_connect_unix_sock(kconsumerd_cmd_unix_sock_path
);
343 if (kconsumerd_cmd_sock
< 0) {
344 sem_post(&kconsumerd_sem
);
345 perror("kconsumerd connect");
348 /* Signal condition to tell that the kconsumerd is ready */
349 sem_post(&kconsumerd_sem
);
350 DBG("Kconsumerd command socket ready");
352 DBG("Kconsumerd error when waiting for SOCK_READY : %s",
353 lttcomm_get_readable_code(-code
));
357 /* Wait for any kconsumerd error */
358 ret
= lttcomm_recv_unix_sock(sock
, &code
, sizeof(enum lttcomm_return_code
));
360 ERR("Kconsumerd closed the command socket");
364 ERR("Kconsumerd return code : %s", lttcomm_get_readable_code(-code
));
368 DBG("Kconsumerd thread dying");
375 * This thread manage the application socket communication
377 static void *thread_manage_apps(void *data
)
381 /* TODO: Something more elegant is needed but fine for now */
382 /* FIXME: change all types to either uint8_t, uint32_t, uint64_t
383 * for 32-bit vs 64-bit compat processes. */
384 /* replicate in ust with version number */
386 int reg
; /* 1:register, 0:unregister */
391 DBG("[thread] Manage apps started");
393 ret
= lttcomm_listen_unix_sock(apps_sock
);
398 /* Notify all applications to register */
399 notify_apps(default_global_apps_pipe
);
402 DBG("Accepting application registration");
403 /* Blocking call, waiting for transmission */
404 sock
= lttcomm_accept_unix_sock(apps_sock
);
409 /* Basic recv here to handle the very simple data
410 * that the libust send to register (reg_msg).
412 ret
= recv(sock
, ®_msg
, sizeof(reg_msg
), 0);
418 /* Add application to the global traceable list */
419 if (reg_msg
.reg
== 1) {
421 ret
= register_traceable_app(reg_msg
.pid
, reg_msg
.uid
);
423 /* register_traceable_app only return an error with
424 * ENOMEM. At this point, we better stop everything.
430 unregister_traceable_app(reg_msg
.pid
);
440 * spawn_kconsumerd_thread
442 * Start the thread_manage_kconsumerd. This must be done after a kconsumerd
443 * exec or it will fails.
445 static int spawn_kconsumerd_thread(void)
449 /* Setup semaphore */
450 sem_init(&kconsumerd_sem
, 0, 0);
452 ret
= pthread_create(&kconsumerd_thread
, NULL
, thread_manage_kconsumerd
, (void *) NULL
);
454 perror("pthread_create kconsumerd");
458 /* Wait for the kconsumerd thread to be ready */
459 sem_wait(&kconsumerd_sem
);
461 if (kconsumerd_pid
== 0) {
462 ERR("Kconsumerd did not start");
469 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
476 * Fork and exec a kernel consumer daemon (kconsumerd).
478 * NOTE: It is very important to fork a kconsumerd BEFORE opening any kernel
479 * file descriptor using the libkernelctl or kernel-ctl functions. So, a
480 * kernel consumer MUST only be spawned before creating a kernel session.
482 * Return pid if successful else -1.
484 static pid_t
spawn_kconsumerd(void)
489 DBG("Spawning kconsumerd");
496 execlp("kconsumerd", "kconsumerd", "--verbose", NULL
);
498 perror("kernel start consumer exec");
501 } else if (pid
> 0) {
505 perror("kernel start consumer fork");
517 * Spawn the kconsumerd daemon and session daemon thread.
519 static int start_kconsumerd(void)
523 pthread_mutex_lock(&kconsumerd_pid_mutex
);
524 if (kconsumerd_pid
!= 0) {
528 ret
= spawn_kconsumerd();
530 ERR("Spawning kconsumerd failed");
531 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
532 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
536 /* Setting up the global kconsumerd_pid */
537 kconsumerd_pid
= ret
;
538 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
540 DBG("Kconsumerd pid %d", ret
);
542 DBG("Spawning kconsumerd thread");
543 ret
= spawn_kconsumerd_thread();
545 ERR("Fatal error spawning kconsumerd thread");
550 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
558 * send_kconsumerd_fds
560 * Send all stream fds of the kernel session to the consumer.
562 static int send_kconsumerd_fds(int sock
, struct ltt_kernel_session
*session
)
566 struct ltt_kernel_stream
*stream
;
567 struct ltt_kernel_channel
*chan
;
568 struct lttcomm_kconsumerd_header lkh
;
569 struct lttcomm_kconsumerd_msg lkm
;
571 nb_fd
= session
->stream_count_global
;
574 lkh
.payload_size
= (nb_fd
+ 1) * sizeof(struct lttcomm_kconsumerd_msg
);
575 lkh
.cmd_type
= ADD_STREAM
;
577 DBG("Sending kconsumerd header");
579 ret
= lttcomm_send_unix_sock(sock
, &lkh
, sizeof(struct lttcomm_kconsumerd_header
));
581 perror("send kconsumerd header");
585 DBG("Sending metadata stream fd");
587 /* Send metadata stream fd first */
588 lkm
.fd
= session
->metadata_stream_fd
;
589 lkm
.state
= ACTIVE_FD
;
590 lkm
.max_sb_size
= session
->metadata
->conf
->subbuf_size
;
591 strncpy(lkm
.path_name
, session
->metadata
->pathname
, PATH_MAX
);
593 ret
= lttcomm_send_fds_unix_sock(sock
, &lkm
, &lkm
.fd
, 1, sizeof(lkm
));
595 perror("send kconsumerd fd");
599 cds_list_for_each_entry(chan
, &session
->channel_list
.head
, list
) {
600 cds_list_for_each_entry(stream
, &chan
->stream_list
.head
, list
) {
602 lkm
.state
= stream
->state
;
603 lkm
.max_sb_size
= chan
->channel
->subbuf_size
;
604 strncpy(lkm
.path_name
, stream
->pathname
, PATH_MAX
);
606 DBG("Sending fd %d to kconsumerd", lkm
.fd
);
608 ret
= lttcomm_send_fds_unix_sock(sock
, &lkm
, &lkm
.fd
, 1, sizeof(lkm
));
610 perror("send kconsumerd fd");
616 DBG("Kconsumerd fds sent");
627 * Create the trace output directory.
629 static int create_trace_dir(struct ltt_kernel_session
*session
)
632 struct ltt_kernel_channel
*chan
;
634 /* Create all channel directories */
635 cds_list_for_each_entry(chan
, &session
->channel_list
.head
, list
) {
636 DBG("Creating trace directory at %s", chan
->pathname
);
637 // TODO: recursive create dir
638 ret
= mkdir(chan
->pathname
, S_IRWXU
| S_IRWXG
);
640 perror("mkdir trace path");
655 * Setup necessary data for kernel tracer action.
657 static void init_kernel_tracer(void)
659 /* Set the global kernel tracer fd */
660 kernel_tracer_fd
= open(DEFAULT_KERNEL_TRACER_PATH
, O_RDWR
);
661 if (kernel_tracer_fd
< 0) {
662 WARN("No kernel tracer available");
663 kernel_tracer_fd
= 0;
666 DBG("Kernel tracer fd %d", kernel_tracer_fd
);
672 * Process the command requested by the lttng client within the command
673 * context structure. This function make sure that the return structure (llm)
674 * is set and ready for transmission before returning.
676 * Return any error encountered or 0 for success.
678 static int process_client_msg(struct command_ctx
*cmd_ctx
)
682 DBG("Processing client command %d", cmd_ctx
->lsm
->cmd_type
);
684 /* Check command that needs a session */
685 switch (cmd_ctx
->lsm
->cmd_type
) {
686 case LTTNG_CREATE_SESSION
:
687 case LTTNG_LIST_SESSIONS
:
688 case KERNEL_LIST_EVENTS
:
692 cmd_ctx
->session
= find_session_by_uuid(cmd_ctx
->lsm
->session_uuid
);
693 if (cmd_ctx
->session
== NULL
) {
694 ret
= LTTCOMM_SELECT_SESS
;
700 /* Check command for kernel tracing */
701 switch (cmd_ctx
->lsm
->cmd_type
) {
702 case KERNEL_CREATE_SESSION
:
703 case KERNEL_CREATE_CHANNEL
:
704 case KERNEL_CREATE_STREAM
:
705 case KERNEL_DISABLE_EVENT
:
706 case KERNEL_ENABLE_EVENT
:
707 case KERNEL_LIST_EVENTS
:
708 case KERNEL_OPEN_METADATA
:
709 case KERNEL_START_TRACE
:
710 case KERNEL_STOP_TRACE
:
711 /* Kernel tracer check */
712 if (kernel_tracer_fd
== 0) {
713 init_kernel_tracer();
714 if (kernel_tracer_fd
== 0) {
715 ret
= LTTCOMM_KERN_NA
;
722 /* Connect to ust apps if available pid */
723 if (cmd_ctx
->lsm
->pid
> 0) {
724 /* Connect to app using ustctl API */
725 cmd_ctx
->ust_sock
= ust_connect_app(cmd_ctx
->lsm
->pid
);
726 if (cmd_ctx
->ust_sock
< 0) {
727 ret
= LTTCOMM_NO_TRACEABLE
;
732 /* Process by command type */
733 switch (cmd_ctx
->lsm
->cmd_type
) {
734 case KERNEL_CREATE_SESSION
:
736 ret
= setup_lttng_msg(cmd_ctx
, 0);
741 ret
= start_kconsumerd();
746 DBG("Creating kernel session");
748 ret
= kernel_create_session(cmd_ctx
->session
, kernel_tracer_fd
);
750 ret
= LTTCOMM_KERN_SESS_FAIL
;
757 case KERNEL_CREATE_CHANNEL
:
759 ret
= setup_lttng_msg(cmd_ctx
, 0);
764 DBG("Creating kernel channel");
766 ret
= kernel_create_channel(cmd_ctx
->session
->kernel_session
);
769 ret
= LTTCOMM_KERN_CHAN_FAIL
;
776 case KERNEL_ENABLE_EVENT
:
778 /* Setup lttng message with no payload */
779 ret
= setup_lttng_msg(cmd_ctx
, 0);
784 DBG("Enabling kernel event %s", cmd_ctx
->lsm
->u
.event
.event_name
);
786 ret
= kernel_enable_event(cmd_ctx
->session
->kernel_session
, cmd_ctx
->lsm
->u
.event
.event_name
);
788 ret
= LTTCOMM_KERN_ENABLE_FAIL
;
795 case KERNEL_ENABLE_ALL_EVENT
:
798 char *event_list
, *event
, *ptr
;
800 /* Setup lttng message with no payload */
801 ret
= setup_lttng_msg(cmd_ctx
, 0);
806 DBG("Enabling all kernel event");
808 size
= kernel_list_events(kernel_tracer_fd
, &event_list
);
810 ret
= LTTCOMM_KERN_LIST_FAIL
;
815 while ((size
= sscanf(ptr
, "event { name = %m[^;]; };%n\n", &event
, &pos
)) == 1) {
816 /* Enable each single event */
817 ret
= kernel_enable_event(cmd_ctx
->session
->kernel_session
, event
);
819 ret
= LTTCOMM_KERN_ENABLE_FAIL
;
822 /* Move pointer to the next line */
832 case KERNEL_LIST_EVENTS
:
837 size
= kernel_list_events(kernel_tracer_fd
, &event_list
);
839 ret
= LTTCOMM_KERN_LIST_FAIL
;
844 * Setup lttng message with payload size set to the event list size in
845 * bytes and then copy list into the llm payload.
847 ret
= setup_lttng_msg(cmd_ctx
, size
);
852 /* Copy event list into message payload */
853 memcpy(cmd_ctx
->llm
->payload
, event_list
, size
);
860 case KERNEL_OPEN_METADATA
:
862 /* Setup lttng message with no payload */
863 ret
= setup_lttng_msg(cmd_ctx
, 0);
868 DBG("Open kernel metadata");
870 ret
= kernel_open_metadata(cmd_ctx
->session
->kernel_session
);
872 ret
= LTTCOMM_KERN_META_FAIL
;
879 case KERNEL_CREATE_STREAM
:
881 struct ltt_kernel_channel
*chan
;
882 /* Setup lttng message with no payload */
883 ret
= setup_lttng_msg(cmd_ctx
, 0);
888 DBG("Creating kernel stream");
890 ret
= kernel_create_metadata_stream(cmd_ctx
->session
->kernel_session
);
892 ERR("Kernel create metadata stream failed");
893 ret
= LTTCOMM_KERN_STREAM_FAIL
;
897 /* For each channel */
898 cds_list_for_each_entry(chan
, &cmd_ctx
->session
->kernel_session
->channel_list
.head
, list
) {
899 ret
= kernel_create_channel_stream(chan
);
901 ERR("Kernel create channel stream failed");
902 ret
= LTTCOMM_KERN_STREAM_FAIL
;
905 /* Update the stream global counter */
906 cmd_ctx
->session
->kernel_session
->stream_count_global
+= ret
;
912 case KERNEL_START_TRACE
:
914 /* Setup lttng message with no payload */
915 ret
= setup_lttng_msg(cmd_ctx
, 0);
920 DBG("Start kernel tracing");
922 ret
= create_trace_dir(cmd_ctx
->session
->kernel_session
);
924 if (ret
== -EEXIST
) {
925 ret
= LTTCOMM_KERN_DIR_EXIST
;
927 ret
= LTTCOMM_KERN_DIR_FAIL
;
932 ret
= kernel_start_session(cmd_ctx
->session
->kernel_session
);
934 ERR("Kernel start session failed");
935 ret
= LTTCOMM_KERN_START_FAIL
;
939 ret
= send_kconsumerd_fds(kconsumerd_cmd_sock
, cmd_ctx
->session
->kernel_session
);
941 ERR("Send kconsumerd fds failed");
942 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
949 case KERNEL_STOP_TRACE
:
951 /* Setup lttng message with no payload */
952 ret
= setup_lttng_msg(cmd_ctx
, 0);
957 if (cmd_ctx
->session
->kernel_session
== NULL
) {
958 ret
= LTTCOMM_KERN_NO_SESSION
;
962 DBG("Stop kernel tracing");
964 ret
= kernel_stop_session(cmd_ctx
->session
->kernel_session
);
966 ERR("Kernel stop session failed");
967 ret
= LTTCOMM_KERN_STOP_FAIL
;
971 /* Clean kernel session teardown */
972 teardown_kernel_session(cmd_ctx
->session
);
977 case LTTNG_CREATE_SESSION
:
979 /* Setup lttng message with no payload */
980 ret
= setup_lttng_msg(cmd_ctx
, 0);
985 ret
= create_session(cmd_ctx
->lsm
->session_name
, &cmd_ctx
->llm
->session_uuid
);
988 ret
= LTTCOMM_EXIST_SESS
;
998 case LTTNG_DESTROY_SESSION
:
1000 /* Setup lttng message with no payload */
1001 ret
= setup_lttng_msg(cmd_ctx
, 0);
1006 ret
= destroy_session(&cmd_ctx
->lsm
->session_uuid
);
1008 ret
= LTTCOMM_NO_SESS
;
1015 case LTTNG_LIST_TRACES
:
1017 unsigned int trace_count
;
1019 trace_count
= get_trace_count_per_session(cmd_ctx
->session
);
1020 if (trace_count
== 0) {
1021 ret
= LTTCOMM_NO_TRACE
;
1025 ret
= setup_lttng_msg(cmd_ctx
, sizeof(struct lttng_trace
) * trace_count
);
1030 get_traces_per_session(cmd_ctx
->session
,
1031 (struct lttng_trace
*)(cmd_ctx
->llm
->payload
));
1036 case UST_CREATE_TRACE
:
1038 /* Setup lttng message with no payload */
1039 ret
= setup_lttng_msg(cmd_ctx
, 0);
1044 ret
= ust_create_trace(cmd_ctx
);
1052 unsigned int app_count
;
1054 app_count
= get_app_count();
1055 DBG("Traceable application count : %d", app_count
);
1056 if (app_count
== 0) {
1057 ret
= LTTCOMM_NO_APPS
;
1061 ret
= setup_lttng_msg(cmd_ctx
, sizeof(pid_t
) * app_count
);
1066 get_app_list_pids((pid_t
*)(cmd_ctx
->llm
->payload
));
1071 case UST_START_TRACE
:
1073 /* Setup lttng message with no payload */
1074 ret
= setup_lttng_msg(cmd_ctx
, 0);
1079 ret
= ust_start_trace(cmd_ctx
);
1085 case UST_STOP_TRACE
:
1087 /* Setup lttng message with no payload */
1088 ret
= setup_lttng_msg(cmd_ctx
, 0);
1093 ret
= ust_stop_trace(cmd_ctx
);
1099 case LTTNG_LIST_SESSIONS
:
1101 unsigned int session_count
;
1103 session_count
= get_session_count();
1104 if (session_count
== 0) {
1105 ret
= LTTCOMM_NO_SESS
;
1109 ret
= setup_lttng_msg(cmd_ctx
, sizeof(struct lttng_session
) * session_count
);
1114 get_lttng_session((struct lttng_session
*)(cmd_ctx
->llm
->payload
));
1120 /* Undefined command */
1121 ret
= setup_lttng_msg(cmd_ctx
, 0);
1130 /* Set return code */
1131 cmd_ctx
->llm
->ret_code
= ret
;
1136 if (cmd_ctx
->llm
== NULL
) {
1137 DBG("Missing llm structure. Allocating one.");
1138 if (setup_lttng_msg(cmd_ctx
, 0) < 0) {
1142 /* Notify client of error */
1143 cmd_ctx
->llm
->ret_code
= ret
;
1150 * thread_manage_clients
1152 * This thread manage all clients request using the unix
1153 * client socket for communication.
1155 static void *thread_manage_clients(void *data
)
1158 struct command_ctx
*cmd_ctx
;
1160 DBG("[thread] Manage client started");
1162 ret
= lttcomm_listen_unix_sock(client_sock
);
1167 /* Notify parent pid that we are ready
1168 * to accept command for client side.
1170 if (opt_sig_parent
) {
1171 kill(ppid
, SIGCHLD
);
1175 /* Blocking call, waiting for transmission */
1176 DBG("Accepting client command ...");
1177 sock
= lttcomm_accept_unix_sock(client_sock
);
1182 /* Allocate context command to process the client request */
1183 cmd_ctx
= malloc(sizeof(struct command_ctx
));
1185 /* Allocate data buffer for reception */
1186 cmd_ctx
->lsm
= malloc(sizeof(struct lttcomm_session_msg
));
1187 cmd_ctx
->llm
= NULL
;
1188 cmd_ctx
->session
= NULL
;
1191 * Data is received from the lttng client. The struct
1192 * lttcomm_session_msg (lsm) contains the command and data request of
1195 DBG("Receiving data from client ...");
1196 ret
= lttcomm_recv_unix_sock(sock
, cmd_ctx
->lsm
, sizeof(struct lttcomm_session_msg
));
1201 // TODO: Validate cmd_ctx including sanity check for security purpose.
1204 * This function dispatch the work to the kernel or userspace tracer
1205 * libs and fill the lttcomm_lttng_msg data structure of all the needed
1206 * informations for the client. The command context struct contains
1207 * everything this function may needs.
1209 ret
= process_client_msg(cmd_ctx
);
1211 /* TODO: Inform client somehow of the fatal error. At this point,
1212 * ret < 0 means that a malloc failed (ENOMEM). */
1213 /* Error detected but still accept command */
1214 clean_command_ctx(cmd_ctx
);
1218 DBG("Sending response (size: %d, retcode: %d)",
1219 cmd_ctx
->lttng_msg_size
, cmd_ctx
->llm
->ret_code
);
1220 ret
= send_unix_sock(sock
, cmd_ctx
->llm
, cmd_ctx
->lttng_msg_size
);
1222 ERR("Failed to send data back to client");
1225 clean_command_ctx(cmd_ctx
);
1227 /* End of transmission */
1237 * usage function on stderr
1239 static void usage(void)
1241 fprintf(stderr
, "Usage: %s OPTIONS\n\nOptions:\n", progname
);
1242 fprintf(stderr
, " -h, --help Display this usage.\n");
1243 fprintf(stderr
, " -c, --client-sock PATH Specify path for the client unix socket\n");
1244 fprintf(stderr
, " -a, --apps-sock PATH Specify path for apps unix socket\n");
1245 fprintf(stderr
, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
1246 fprintf(stderr
, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
1247 fprintf(stderr
, " -d, --daemonize Start as a daemon.\n");
1248 fprintf(stderr
, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
1249 fprintf(stderr
, " -V, --version Show version number.\n");
1250 fprintf(stderr
, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
1251 fprintf(stderr
, " -q, --quiet No output at all.\n");
1252 fprintf(stderr
, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
1256 * daemon argument parsing
1258 static int parse_args(int argc
, char **argv
)
1262 static struct option long_options
[] = {
1263 { "client-sock", 1, 0, 'c' },
1264 { "apps-sock", 1, 0, 'a' },
1265 { "kconsumerd-cmd-sock", 1, 0, 0 },
1266 { "kconsumerd-err-sock", 1, 0, 0 },
1267 { "daemonize", 0, 0, 'd' },
1268 { "sig-parent", 0, 0, 'S' },
1269 { "help", 0, 0, 'h' },
1270 { "group", 1, 0, 'g' },
1271 { "version", 0, 0, 'V' },
1272 { "quiet", 0, 0, 'q' },
1273 { "verbose", 0, 0, 'v' },
1278 int option_index
= 0;
1279 c
= getopt_long(argc
, argv
, "dhqvVS" "a:c:g:s:E:C:", long_options
, &option_index
);
1286 fprintf(stderr
, "option %s", long_options
[option_index
].name
);
1288 fprintf(stderr
, " with arg %s\n", optarg
);
1292 snprintf(client_unix_sock_path
, PATH_MAX
, "%s", optarg
);
1295 snprintf(apps_unix_sock_path
, PATH_MAX
, "%s", optarg
);
1301 opt_tracing_group
= strdup(optarg
);
1307 fprintf(stdout
, "%s\n", VERSION
);
1313 snprintf(kconsumerd_err_unix_sock_path
, PATH_MAX
, "%s", optarg
);
1316 snprintf(kconsumerd_cmd_unix_sock_path
, PATH_MAX
, "%s", optarg
);
1325 /* Unknown option or other error.
1326 * Error is printed by getopt, just return */
1335 * init_daemon_socket
1337 * Creates the two needed socket by the daemon.
1338 * apps_sock - The communication socket for all UST apps.
1339 * client_sock - The communication of the cli tool (lttng).
1341 static int init_daemon_socket()
1346 old_umask
= umask(0);
1348 /* Create client tool unix socket */
1349 client_sock
= lttcomm_create_unix_sock(client_unix_sock_path
);
1350 if (client_sock
< 0) {
1351 ERR("Create unix sock failed: %s", client_unix_sock_path
);
1356 /* File permission MUST be 660 */
1357 ret
= chmod(client_unix_sock_path
, S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
);
1359 ERR("Set file permissions failed: %s", client_unix_sock_path
);
1364 /* Create the application unix socket */
1365 apps_sock
= lttcomm_create_unix_sock(apps_unix_sock_path
);
1366 if (apps_sock
< 0) {
1367 ERR("Create unix sock failed: %s", apps_unix_sock_path
);
1372 /* File permission MUST be 666 */
1373 ret
= chmod(apps_unix_sock_path
, S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
| S_IROTH
| S_IWOTH
);
1375 ERR("Set file permissions failed: %s", apps_unix_sock_path
);
1386 * check_existing_daemon
1388 * Check if the global socket is available.
1389 * If yes, error is returned.
1391 static int check_existing_daemon()
1395 ret
= access(client_unix_sock_path
, F_OK
);
1397 ret
= access(apps_unix_sock_path
, F_OK
);
1406 * Return pointer to home directory path using
1407 * the env variable HOME.
1411 static const char *get_home_dir(void)
1413 const char *home_path
;
1415 if ((home_path
= (const char *) getenv("HOME")) == NULL
) {
1416 home_path
= default_home_dir
;
1425 * Set the tracing group gid onto the client socket.
1427 * Race window between mkdir and chown is OK because we are going from
1428 * less permissive (root.root) to more permissive (root.tracing).
1430 static int set_permissions(void)
1435 /* Decide which group name to use */
1436 (opt_tracing_group
!= NULL
) ?
1437 (grp
= getgrnam(opt_tracing_group
)) :
1438 (grp
= getgrnam(default_tracing_group
));
1441 ERR("Missing tracing group. Aborting execution.\n");
1446 /* Set lttng run dir */
1447 ret
= chown(LTTNG_RUNDIR
, 0, grp
->gr_gid
);
1449 ERR("Unable to set group on " LTTNG_RUNDIR
);
1453 /* lttng client socket path */
1454 ret
= chown(client_unix_sock_path
, 0, grp
->gr_gid
);
1456 ERR("Unable to set group on %s", client_unix_sock_path
);
1460 /* kconsumerd error socket path */
1461 ret
= chown(kconsumerd_err_unix_sock_path
, 0, grp
->gr_gid
);
1463 ERR("Unable to set group on %s", kconsumerd_err_unix_sock_path
);
1467 DBG("All permissions are set");
1474 * create_lttng_rundir
1476 * Create the lttng run directory needed for all
1477 * global sockets and pipe.
1479 static int create_lttng_rundir(void)
1483 ret
= mkdir(LTTNG_RUNDIR
, S_IRWXU
| S_IRWXG
);
1485 if (errno
!= EEXIST
) {
1486 ERR("Unable to create " LTTNG_RUNDIR
);
1498 * set_kconsumerd_sockets
1500 * Setup sockets and directory needed by the kconsumerd
1501 * communication with the session daemon.
1503 static int set_kconsumerd_sockets(void)
1507 if (strlen(kconsumerd_err_unix_sock_path
) == 0) {
1508 snprintf(kconsumerd_err_unix_sock_path
, PATH_MAX
, KCONSUMERD_ERR_SOCK_PATH
);
1511 if (strlen(kconsumerd_cmd_unix_sock_path
) == 0) {
1512 snprintf(kconsumerd_cmd_unix_sock_path
, PATH_MAX
, KCONSUMERD_CMD_SOCK_PATH
);
1515 ret
= mkdir(KCONSUMERD_PATH
, S_IRWXU
| S_IRWXG
);
1517 ERR("Failed to create " KCONSUMERD_PATH
);
1521 /* Create the kconsumerd error unix socket */
1522 kconsumerd_err_sock
= lttcomm_create_unix_sock(kconsumerd_err_unix_sock_path
);
1523 if (kconsumerd_err_sock
< 0) {
1524 ERR("Create unix sock failed: %s", kconsumerd_err_unix_sock_path
);
1529 /* File permission MUST be 660 */
1530 ret
= chmod(kconsumerd_err_unix_sock_path
, S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
);
1532 ERR("Set file permissions failed: %s", kconsumerd_err_unix_sock_path
);
1544 * Signal handler for the daemon
1546 static void sighandler(int sig
)
1550 DBG("SIGPIPE catched");
1553 DBG("SIGINT catched");
1557 DBG("SIGTERM catched");
1568 * set_signal_handler
1570 * Setup signal handler for :
1571 * SIGINT, SIGTERM, SIGPIPE
1573 static int set_signal_handler(void)
1576 struct sigaction sa
;
1579 if ((ret
= sigemptyset(&sigset
)) < 0) {
1580 perror("sigemptyset");
1584 sa
.sa_handler
= sighandler
;
1585 sa
.sa_mask
= sigset
;
1587 if ((ret
= sigaction(SIGTERM
, &sa
, NULL
)) < 0) {
1588 perror("sigaction");
1592 if ((ret
= sigaction(SIGINT
, &sa
, NULL
)) < 0) {
1593 perror("sigaction");
1597 if ((ret
= sigaction(SIGPIPE
, &sa
, NULL
)) < 0) {
1598 perror("sigaction");
1602 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
1610 int main(int argc
, char **argv
)
1615 /* Parse arguments */
1617 if ((ret
= parse_args(argc
, argv
) < 0)) {
1630 /* Check if daemon is UID = 0 */
1631 is_root
= !getuid();
1633 /* Set all sockets path */
1635 ret
= create_lttng_rundir();
1640 if (strlen(apps_unix_sock_path
) == 0) {
1641 snprintf(apps_unix_sock_path
, PATH_MAX
,
1642 DEFAULT_GLOBAL_APPS_UNIX_SOCK
);
1645 if (strlen(client_unix_sock_path
) == 0) {
1646 snprintf(client_unix_sock_path
, PATH_MAX
,
1647 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK
);
1650 ret
= set_kconsumerd_sockets();
1655 /* Setup kernel tracer */
1656 init_kernel_tracer();
1658 if (strlen(apps_unix_sock_path
) == 0) {
1659 snprintf(apps_unix_sock_path
, PATH_MAX
,
1660 DEFAULT_HOME_APPS_UNIX_SOCK
, get_home_dir());
1663 /* Set the cli tool unix socket path */
1664 if (strlen(client_unix_sock_path
) == 0) {
1665 snprintf(client_unix_sock_path
, PATH_MAX
,
1666 DEFAULT_HOME_CLIENT_UNIX_SOCK
, get_home_dir());
1670 DBG("Client socket path %s", client_unix_sock_path
);
1671 DBG("Application socket path %s", apps_unix_sock_path
);
1673 /* See if daemon already exist. If any of the two
1674 * socket needed by the daemon are present, this test fails
1676 if ((ret
= check_existing_daemon()) == 0) {
1677 ERR("Already running daemon.\n");
1678 /* We do not goto error because we must not
1679 * cleanup() because a daemon is already running.
1684 if (set_signal_handler() < 0) {
1688 /* Setup the needed unix socket */
1689 if (init_daemon_socket() < 0) {
1693 /* Set credentials to socket */
1694 if (is_root
&& (set_permissions() < 0)) {
1698 /* Get parent pid if -S, --sig-parent is specified. */
1699 if (opt_sig_parent
) {
1704 /* Create thread to manage the client socket */
1705 ret
= pthread_create(&client_thread
, NULL
, thread_manage_clients
, (void *) NULL
);
1707 perror("pthread_create");
1711 /* Create thread to manage application socket */
1712 ret
= pthread_create(&apps_thread
, NULL
, thread_manage_apps
, (void *) NULL
);
1714 perror("pthread_create");
1718 ret
= pthread_join(client_thread
, &status
);
1720 perror("pthread_join");