#ifndef _LIBLTTNGCTL_H
#define _LIBLTTNGCTL_H
+/* Default unix group name for tracing.
+ */
#define DEFAULT_TRACING_GROUP "tracing"
+/* Environment variable to set session daemon
+ * binary path.
+ */
+#define LTTNG_SESSIOND_PATH_ENV "LTTNG_SESSIOND_PATH"
+
/*
* From libuuid
*/
/* Variables */
const char *progname;
const char *opt_tracing_group;
+static int opt_sig_parent;
static int opt_daemon;
static int is_root; /* Set to 1 if the daemon is running as root */
+static pid_t ppid;
static char apps_unix_sock_path[PATH_MAX]; /* Global application Unix socket path */
static char client_unix_sock_path[PATH_MAX]; /* Global client Unix socket path */
goto error;
}
+ /* Notify parent pid that we are ready
+ * to accept command for client side.
+ */
+ if (opt_sig_parent) {
+ kill(ppid, SIGCHLD);
+ }
+
while (1) {
/* Blocking call, waiting for transmission */
sock = lttcomm_accept_unix_sock(client_socket);
"\t-a, --apps-sock PATH\t\tSpecify path for apps unix socket.\n"
"\t-d, --daemonize\t\tStart as a daemon.\n"
"\t-g, --group NAME\t\tSpecify the tracing group name. (default: tracing)\n"
- "\t-V, --version\t\tShow version number.\n",
+ "\t-V, --version\t\tShow version number.\n"
+ "\t-S, --sig-parent\t\tSend SIGCHLD to parent pid to notify readiness.\n",
progname);
}
{ "client-sock", 1, 0, 'c' },
{ "apps-sock", 1, 0, 'a' },
{ "daemonize", 0, 0, 'd' },
+ { "sig-parent", 0, 0, 'S' },
{ "help", 0, 0, 'h' },
{ "group", 1, 0, 'g' },
{ "version", 0, 0, 'V' },
while (1) {
int option_index = 0;
- c = getopt_long(argc, argv, "dhV" "a:c:g:s:", long_options, &option_index);
+ c = getopt_long(argc, argv, "dhVS" "a:c:g:s:", long_options, &option_index);
if (c == -1) {
break;
}
case 'V':
fprintf(stdout, "%s\n", VERSION);
exit(EXIT_SUCCESS);
+ case 'S':
+ opt_sig_parent = 1;
+ break;
default:
/* Unknown option or other error.
* Error is printed by getopt, just return */
goto error;
}
+ /* Get parent pid if -S, --sig-parent is specified. */
+ if (opt_sig_parent) {
+ ppid = getppid();
+ }
+
while (1) {
/* Create thread to manage the client socket */
ret = pthread_create(&threads[0], NULL, thread_manage_clients, (void *) NULL);
/* Prototypes */
static int process_client_opt(void);
static int process_opt_list_apps(void);
+static void sighandler(int sig);
+static int set_signal_handler(void);
/*
* start_client
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;
}
extern int opt_quiet;
extern char *opt_tracing_group;
extern char *opt_session_name;
+extern char *opt_sessiond_path;
extern int opt_list_apps;
+extern int opt_no_sessiond;
+
+#define SESSIOND_PATH_NUM 6
#endif /* _LTTNG_H */
/* Option variables */
char *opt_tracing_group;
char *opt_session_name;
+char *opt_sessiond_path;
int opt_trace_kernel = 0;
int opt_quiet = 0;
int opt_verbose = 0;
int opt_list_apps = 0;
+int opt_no_sessiond = 0;
enum {
OPT_HELP = 42,
{"quiet", 'q', POPT_ARG_VAL, &opt_quiet, 1, 0},
{"verbose", 'v', POPT_ARG_VAL, &opt_verbose, 1, 0},
{"list-apps", 'l', POPT_ARG_VAL, &opt_list_apps, 1, 0},
+ {"no-sessiond", 0, POPT_ARG_VAL, &opt_no_sessiond, 1, 0},
+ {"sessiond-path", 0, POPT_ARG_STRING, &opt_sessiond_path, 0, 0},
{0, 0, 0, 0, 0, 0}
};
fprintf(ofp, " -q, --quiet Quiet mode\n");
fprintf(ofp, " --help Show help\n");
fprintf(ofp, " --group NAME Unix tracing group name. (default: tracing)\n");
+ fprintf(ofp, " --no-sessiond Don't spawn a session daemon.\n");
+ fprintf(ofp, " --sessiond-path Session daemon full path\n");
fprintf(ofp, "\n");
fprintf(ofp, "Tracing options:\n");
//fprintf(ofp, " --session [NAME] Specify tracing session. If no NAME is given\n");
projects / lttng-tools.git / commitdiff
