+static int add_container_getty(const char *tty) {
+ _cleanup_free_ char *n = NULL;
+
+ assert(tty);
+
+ log_debug("Automatically adding container getty for /dev/pts/%s.", tty);
+
+ n = unit_name_from_path_instance("container-getty", tty, ".service");
+ if (!n)
+ return log_oom();
+
+ return add_symlink("container-getty@.service", n);
+}
+
+static int verify_tty(const char *name) {
+ _cleanup_close_ int fd = -1;
+ const char *p;
+
+ /* Some TTYs are weird and have been enumerated but don't work
+ * when you try to use them, such as classic ttyS0 and
+ * friends. Let's check that and open the device and run
+ * isatty() on it. */
+
+ p = strappenda("/dev/", name);
+
+ /* O_NONBLOCK is essential here, to make sure we don't wait
+ * for DCD */
+ fd = open(p, O_RDWR|O_NONBLOCK|O_NOCTTY|O_CLOEXEC|O_NOFOLLOW);
+ if (fd < 0)
+ return -errno;
+
+ errno = 0;
+ if (isatty(fd) <= 0)
+ return errno ? -errno : -EIO;
+
+ return 0;