is_good_installation_id (const char *id)
{
  if (strcmp (id, "") == 0 ||
      strcmp (id, "user") == 0 ||
      strcmp (id, SYSTEM_DIR_DEFAULT_ID) == 0 ||
      strcmp (id, "system") == 0)
    return FALSE;

  if (!g_str_is_ascii (id) ||
      strpbrk (id, " /\n"))
    return FALSE;

  if (strlen (id) > 80)
    return FALSE;

  return TRUE;
}
is_good_installation_id (const char *id)
{
  if (strcmp (id, "") == 0 ||
      strcmp (id, "user") == 0 ||
      strcmp (id, SYSTEM_DIR_DEFAULT_ID) == 0 ||
      strcmp (id, "system") == 0)
    return FALSE;

  if (!g_str_is_ascii (id) ||
      strpbrk (id, " /\n"))
    return FALSE;

  if (strlen (id) > 80)
    return FALSE;

  return TRUE;
}