+
+int generator_write_timeouts(const char *dir, const char *what, const char *where,
+ const char *opts, char **filtered) {
+
+ /* Allow configuration how long we wait for a device that
+ * backs a mount point to show up. This is useful to support
+ * endless device timeouts for devices that show up only after
+ * user input, like crypto devices. */
+
+ _cleanup_free_ char *node = NULL, *unit = NULL, *t = NULL;
+ char *start, *timeout;
+ usec_t u;
+ int r;
+ size_t len;
+
+ if ((start = mount_test_option(opts, "comment=systemd.device-timeout")))
+ timeout = start + 31;
+ else if ((start = mount_test_option(opts, "x-systemd.device-timeout")))
+ timeout = start + 25;
+ else {
+ if (filtered) {
+ *filtered = strdup(opts ?: "");
+ if (!*filtered)
+ return log_oom();
+ }
+
+ return 0;
+ }
+
+ len = strcspn(timeout, ",;" WHITESPACE);
+ t = strndup(timeout, len);
+ if (!t)
+ return -ENOMEM;
+
+ if (filtered) {
+ char *prefix, *postfix;
+
+ prefix = strndupa(opts, start - opts - (start != opts));
+ postfix = timeout + len + (start == opts && timeout[len] != '\0');
+ *filtered = strjoin(prefix, *postfix ? postfix : NULL, NULL);
+ if (!*filtered)
+ return log_oom();
+ }
+
+ r = parse_sec(t, &u);
+ if (r < 0) {
+ log_warning("Failed to parse timeout for %s, ignoring: %s",
+ where, timeout);
+ return 0;
+ }
+
+ node = fstab_node_to_udev_node(what);
+ if (!node)
+ return log_oom();
+
+ unit = unit_name_from_path(node, ".device");
+ if (!unit)
+ return -ENOMEM;
+
+ return write_drop_in_format(dir, unit, 50, "device-timeout",
+ "# Automatically generated by %s\n\n"
+ "[Unit]\nJobTimeoutSec=" USEC_FMT,
+ program_invocation_short_name,
+ u / USEC_PER_SEC);
+}