X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fmain.c;h=37c7354ef0827f22fd23a1f53c2a71464fb18c1a;hb=72dd74910ee17be5d82c6b2286f454942bf19d24;hp=21654957aac170fc0f17c5b86496ecfdc7e94eae;hpb=97bc1426a470ac30ed29357e5c68a256a79fef0e;p=lttng-tools.git

diff --git a/src/bin/lttng-sessiond/main.c b/src/bin/lttng-sessiond/main.c
index 21654957a..37c7354ef 100644
--- a/src/bin/lttng-sessiond/main.c
+++ b/src/bin/lttng-sessiond/main.c
@@ -46,6 +46,7 @@
 #include <common/futex.h>
 #include <common/relayd/relayd.h>
 #include <common/utils.h>
+#include <common/daemonize.h>
 #include <common/config/config.h>
 
 #include "lttng-sessiond.h"
@@ -76,7 +77,7 @@ static int tracing_group_name_override;
 static char *opt_pidfile;
 static int opt_sig_parent;
 static int opt_verbose_consumer;
-static int opt_daemon;
+static int opt_daemon, opt_background;
 static int opt_no_kernel;
 static int is_root;			/* Set to 1 if the daemon is running as root */
 static pid_t ppid;          /* Parent PID for --sig-parent option */
@@ -139,6 +140,7 @@ static const struct option long_options[] = {
 	{ "consumerd64-path", 1, 0, 't' },
 	{ "consumerd64-libdir", 1, 0, 'T' },
 	{ "daemonize", 0, 0, 'd' },
+	{ "background", 0, 0, 'b' },
 	{ "sig-parent", 0, 0, 'S' },
 	{ "help", 0, 0, 'h' },
 	{ "group", 1, 0, 'g' },
@@ -310,7 +312,7 @@ void lttng_sessiond_notify_ready(void)
 		 * Notify the parent of the fork() process that we are
 		 * ready.
 		 */
-		if (opt_daemon) {
+		if (opt_daemon || opt_background) {
 			kill(child_ppid, SIGUSR1);
 		}
 	}
@@ -4038,6 +4040,7 @@ static void usage(void)
 	fprintf(stderr, "      --consumerd64-path PATH     Specify path for the 64-bit UST consumer daemon binary\n");
 	fprintf(stderr, "      --consumerd64-libdir PATH   Specify path for the 64-bit UST consumer daemon libraries\n");
 	fprintf(stderr, "  -d, --daemonize                    Start as a daemon.\n");
+	fprintf(stderr, "  -b, --background                   Start as a daemon, keeping console open.\n");
 	fprintf(stderr, "  -g, --group NAME                   Specify the tracing group name. (default: tracing)\n");
 	fprintf(stderr, "  -V, --version                      Show version number.\n");
 	fprintf(stderr, "  -S, --sig-parent                   Send SIGUSR1 to parent pid to notify readiness.\n");
@@ -4076,6 +4079,9 @@ static int set_option(int opt, const char *arg, const char *optname)
 	case 'd':
 		opt_daemon = 1;
 		break;
+	case 'b':
+		opt_background = 1;
+		break;
 	case 'g':
 		tracing_group_name = strdup(arg);
 		break;
@@ -4691,107 +4697,6 @@ error:
 	return;
 }
 
-/*
- * Daemonize this process by forking and making the parent wait for the child
- * to signal it indicating readiness. Once received, the parent successfully
- * quits.
- *
- * The child process undergoes the same action that daemon(3) does meaning
- * setsid, chdir, and dup /dev/null into 0, 1 and 2.
- *
- * Return 0 on success else -1 on error.
- */
-static int daemonize(void)
-{
-	int ret;
-	pid_t pid;
-
-	/* Get parent pid of this process. */
-	child_ppid = getppid();
-
-	pid = fork();
-	if (pid < 0) {
-		PERROR("fork");
-		goto error;
-	} else if (pid == 0) {
-		int fd;
-		pid_t sid;
-
-		/* Child */
-
-		/*
-		 * Get the newly created parent pid so we can signal that process when
-		 * we are ready to operate.
-		 */
-		child_ppid = getppid();
-
-		sid = setsid();
-		if (sid < 0) {
-			PERROR("setsid");
-			goto error;
-		}
-
-		/* Try to change directory to /. If we can't well at least notify. */
-		ret = chdir("/");
-		if (ret < 0) {
-			PERROR("chdir");
-		}
-
-		fd = open(_PATH_DEVNULL, O_RDWR, 0);
-		if (fd < 0) {
-			PERROR("open %s", _PATH_DEVNULL);
-			/* Let 0, 1 and 2 open since we can't bind them to /dev/null. */
-		} else {
-			(void) dup2(fd, STDIN_FILENO);
-			(void) dup2(fd, STDOUT_FILENO);
-			(void) dup2(fd, STDERR_FILENO);
-			if (fd > 2) {
-				ret = close(fd);
-				if (ret < 0) {
-					PERROR("close");
-				}
-			}
-		}
-		goto end;
-	} else {
-		/* Parent */
-
-		/*
-		 * Waiting for child to notify this parent that it can exit. Note that
-		 * sleep() is interrupted before the 1 second delay as soon as the
-		 * signal is received, so it will not cause visible delay for the
-		 * user.
-		 */
-		while (!CMM_LOAD_SHARED(recv_child_signal)) {
-			int status;
-			pid_t ret;
-
-			/*
-			 * Check if child exists without blocking. If so, we have to stop
-			 * this parent process and return an error.
-			 */
-			ret = waitpid(pid, &status, WNOHANG);
-			if (ret < 0 || (ret != 0 && WIFEXITED(status))) {
-				/* The child exited somehow or was not valid. */
-				goto error;
-			}
-			sleep(1);
-		}
-
-		/*
-		 * From this point on, the parent can exit and the child is now an
-		 * operationnal session daemon ready to serve clients and applications.
-		 */
-		exit(EXIT_SUCCESS);
-	}
-
-end:
-	return 0;
-
-error:
-	return -1;
-}
-
 /*
  * main
  */
@@ -4825,10 +4730,11 @@ int main(int argc, char **argv)
 	}
 
 	/* Daemonize */
-	if (opt_daemon) {
+	if (opt_daemon || opt_background) {
 		int i;
 
-		ret = daemonize();
+		ret = lttng_daemonize(&child_ppid, &recv_child_signal,
+			!opt_background);
 		if (ret < 0) {
 			goto error;
 		}