-/* Copyright (c) 2011 David Goulet <david.goulet@polymtl.ca>
+/*
+ * Copyright (c) 2011 David Goulet <david.goulet@polymtl.ca>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
- *
*/
#define _GNU_SOURCE
/* Prototypes */
static int process_client_opt(void);
static int process_opt_list_apps(void);
+static int process_opt_list_sessions(void);
+static void sighandler(int sig);
+static int set_signal_handler(void);
/*
* start_client
/* Connect to the session daemon */
ret = lttng_connect_sessiond();
if (ret < 0) {
- ERR("%s", lttng_get_readable_code(ret));
goto end;
}
if (opt_list_apps) {
ret = process_opt_list_apps();
if (ret < 0) {
- ERR("%s", lttng_get_readable_code(ret));
+ goto end;
+ }
+ }
+
+ if (opt_list_session) {
+ ret = process_opt_list_sessions();
+ if (ret < 0) {
goto end;
}
}
return 0;
end:
+ ERR("%s", lttng_get_readable_code(ret));
+ return ret;
+}
+
+/*
+ * process_opt_list_sessions
+ *
+ * Get the list of available sessions from
+ * the session daemon and print it to user.
+ */
+static int process_opt_list_sessions(void)
+{
+ int ret, count, i;
+ struct lttng_session *sess;
+
+ count = lttng_list_sessions(&sess);
+ if (count < 0) {
+ ret = count;
+ goto error;
+ }
+
+ MSG("Available sessions [Name (uuid)]:");
+ for (i = 0; i < count; i++) {
+ MSG("\tName: %s (uuid: %s)", sess[i].name, sess[i].uuid);
+ }
+
+ free(sess);
+ MSG("\nTo select a session, use --session UUID.");
+
+ return 0;
+
+error:
return ret;
}
fclose(fp);
}
+ /* Allocated by lttng_ust_list_apps() */
+ free(pids);
+
return 0;
error:
return ret;
}
+/*
+ * spawn_sessiond
+ *
+ * Spawn a session daemon by forking and execv.
+ */
+static int spawn_sessiond(char *pathname)
+{
+ int ret = 0;
+ pid_t pid;
+
+ MSG("Spawning session daemon");
+ pid = fork();
+ if (pid == 0) {
+ /* Spawn session daemon and tell
+ * it to signal us when ready.
+ */
+ ret = execlp(pathname, "ltt-sessiond", "--sig-parent", NULL);
+ if (ret < 0) {
+ if (errno == ENOENT) {
+ ERR("No session daemon found. Use --sessiond-path.");
+ } else {
+ perror("execlp");
+ }
+ kill(getppid(), SIGTERM);
+ exit(EXIT_FAILURE);
+ }
+ exit(EXIT_SUCCESS);
+ } else if (pid > 0) {
+ /* Wait for ltt-sessiond to start */
+ pause();
+ goto end;
+ } else {
+ perror("fork");
+ ret = -1;
+ goto end;
+ }
+
+end:
+ return ret;
+}
+
/*
* check_ltt_sessiond
*
* Check if the session daemon is available using
- * the liblttngctl API for the check.
+ * the liblttngctl API for the check. If not, try to
+ * spawn a daemon.
*/
static int check_ltt_sessiond(void)
{
int ret;
+ char *pathname = NULL;
ret = lttng_check_session_daemon();
if (ret < 0) {
- ERR("No session daemon found. Aborting.");
+ /* Try command line option path */
+ if (opt_sessiond_path != NULL) {
+ ret = access(opt_sessiond_path, F_OK | X_OK);
+ if (ret < 0) {
+ ERR("No such file: %s", opt_sessiond_path);
+ goto end;
+ }
+ pathname = opt_sessiond_path;
+ } else {
+ /* Try LTTNG_SESSIOND_PATH env variable */
+ pathname = strdup(getenv(LTTNG_SESSIOND_PATH_ENV));
+ }
+
+ /* Let's rock and roll */
+ if (pathname == NULL) {
+ ret = asprintf(&pathname, "ltt-sessiond");
+ if (ret < 0) {
+ goto end;
+ }
+ }
+
+ ret = spawn_sessiond(pathname);
+ free(pathname);
+ if (ret < 0) {
+ ERR("Problem occurs when starting %s", pathname);
+ goto end;
+ }
+ }
+
+end:
+ return ret;
+}
+
+/*
+ * set_signal_handler
+ *
+ * Setup signal handler for SIGCHLD and SIGTERM.
+ */
+static int set_signal_handler(void)
+{
+ int ret = 0;
+ struct sigaction sa;
+ sigset_t sigset;
+
+ if ((ret = sigemptyset(&sigset)) < 0) {
+ perror("sigemptyset");
+ goto end;
+ }
+
+ sa.sa_handler = sighandler;
+ sa.sa_mask = sigset;
+ sa.sa_flags = 0;
+ if ((ret = sigaction(SIGCHLD, &sa, NULL)) < 0) {
+ perror("sigaction");
+ goto end;
}
+ if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
+ perror("sigaction");
+ goto end;
+ }
+
+end:
return ret;
}
+/*
+ * sighandler
+ *
+ * Signal handler for the daemon
+ */
+static void sighandler(int sig)
+{
+ DBG("%d received", sig);
+ switch (sig) {
+ case SIGTERM:
+ clean_exit(EXIT_FAILURE);
+ break;
+ case SIGCHLD:
+ /* Notify is done */
+ break;
+ default:
+ break;
+ }
+ return;
+}
/*
* clean_exit
*/
}
/*
- * main
+ * main
*/
int main(int argc, char *argv[])
{
return EXIT_FAILURE;
}
+ ret = set_signal_handler();
+ if (ret < 0) {
+ return ret;
+ }
+
if (opt_tracing_group != NULL) {
DBG("Set tracing group to '%s'", opt_tracing_group);
lttng_set_tracing_group(opt_tracing_group);
/* Check if the lttng session daemon is running.
* If no, a daemon will be spawned.
*/
- if (check_ltt_sessiond() < 0) {
+ if (opt_no_sessiond == 0 && (check_ltt_sessiond() < 0)) {
return EXIT_FAILURE;
}