fix restart + -u issue FSCORE-199

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@9892 d0543943-73ff-0310-b7d9-9358b9ac24b2

src/switch_core.c

@@ -564,6 +564,11 @@ SWITCH_DECLARE(int32_t) change_user_group(const char *user, const char *group)
 		runas_gid = gr->gr_gid;
 	}
 
+	if (runas_uid && getuid() == runas_uid && (!runas_gid || runas_gid == getgid())) {
+		/* already running as the right user and group, nothing to do! */
+		return 0;
+	}
+
 	if (runas_uid) {
 #ifdef HAVE_SETGROUPS
 		/*