static gboolean
export_dir (int            source_parent_fd,
            const char    *source_name,
            const char    *source_relpath,
            int            destination_parent_fd,
            const char    *destination_name,
            const char    *required_prefix,
            GCancellable  *cancellable,
            GError       **error)
{
  gboolean ret = FALSE;
  int res;
  g_auto(GLnxDirFdIterator) source_iter = {0};
  glnx_fd_close int destination_dfd = -1;
  struct dirent *dent;

  if (!glnx_dirfd_iterator_init_at (source_parent_fd, source_name, FALSE, &source_iter, error))
    goto out;

  do
    res = mkdirat (destination_parent_fd, destination_name, 0777);
  while (G_UNLIKELY (res == -1 && errno == EINTR));
  if (res == -1)
    {
      if (errno != EEXIST)
        {
          glnx_set_error_from_errno (error);
          goto out;
        }
    }

  if (!gs_file_open_dir_fd_at (destination_parent_fd, destination_name,
                               &destination_dfd,
                               cancellable, error))
    goto out;

  while (TRUE)
    {
      struct stat stbuf;
      g_autofree char *source_printable = NULL;

      if (!glnx_dirfd_iterator_next_dent (&source_iter, &dent, cancellable, error))
        goto out;

      if (dent == NULL)
        break;

      if (fstatat (source_iter.fd, dent->d_name, &stbuf, AT_SYMLINK_NOFOLLOW) == -1)
        {
          if (errno == ENOENT)
            continue;
          else
            {
              glnx_set_error_from_errno (error);
              goto out;
            }
        }

      if (S_ISDIR (stbuf.st_mode))
        {
          g_autofree gchar *child_relpath = g_build_filename(source_relpath, dent->d_name, NULL);

          if (!export_dir (source_iter.fd, dent->d_name, child_relpath, destination_dfd, dent->d_name,
                           required_prefix, cancellable, error))
            goto out;
        }
      else if (S_ISREG (stbuf.st_mode))
        {
          source_printable = g_build_filename (source_relpath, dent->d_name, NULL);


          if (!xdg_app_has_name_prefix (dent->d_name, required_prefix))
            {
              g_print ("Not exporting %s, wrong prefix\n", source_printable);
              continue;
            }

          g_print ("Exporting %s\n", source_printable);

          if (!glnx_file_copy_at (source_iter.fd, dent->d_name, &stbuf,
                                  destination_dfd, dent->d_name,
                                  GLNX_FILE_COPY_NOXATTRS,
                                  cancellable,
                                  error))
            goto out;
        }
      else
        {
          source_printable = g_build_filename (source_relpath, dent->d_name, NULL);
          g_print ("Not exporting non-regular file %s\n", source_printable);
        }
    }

  ret = TRUE;
 out:

  return ret;
}
static gboolean
export_dir (int            source_parent_fd,
            const char    *source_name,
            const char    *source_relpath,
            int            destination_parent_fd,
            const char    *destination_name,
            const char    *required_prefix,
            GCancellable  *cancellable,
            GError       **error)
{
  int res;
  g_auto(GLnxDirFdIterator) source_iter = {0};
  glnx_fd_close int destination_dfd = -1;
  struct dirent *dent;

  if (!glnx_dirfd_iterator_init_at (source_parent_fd, source_name, FALSE, &source_iter, error))
    return FALSE;

  do
    res = mkdirat (destination_parent_fd, destination_name, 0755);
  while (G_UNLIKELY (res == -1 && errno == EINTR));
  if (res == -1)
    {
      if (errno != EEXIST)
        {
          glnx_set_error_from_errno (error);
          return FALSE;
        }
    }

  if (!gs_file_open_dir_fd_at (destination_parent_fd, destination_name,
                               &destination_dfd,
                               cancellable, error))
    return FALSE;

  while (TRUE)
    {
      struct stat stbuf;
      g_autofree char *source_printable = NULL;

      if (!glnx_dirfd_iterator_next_dent (&source_iter, &dent, cancellable, error))
        return FALSE;

      if (dent == NULL)
        break;

      if (fstatat (source_iter.fd, dent->d_name, &stbuf, AT_SYMLINK_NOFOLLOW) == -1)
        {
          if (errno == ENOENT)
            continue;
          else
            {
              glnx_set_error_from_errno (error);
              return FALSE;
            }
        }

      /* Don't export any hidden files or backups */
      if (g_str_has_prefix (dent->d_name, ".") ||
          g_str_has_suffix (dent->d_name, "~"))
        continue;

      if (S_ISDIR (stbuf.st_mode))
        {
          g_autofree gchar *child_relpath = g_build_filename(source_relpath, dent->d_name, NULL);

          if (!export_dir (source_iter.fd, dent->d_name, child_relpath, destination_dfd, dent->d_name,
                           required_prefix, cancellable, error))
            return FALSE;
        }
      else if (S_ISREG (stbuf.st_mode))
        {
          source_printable = g_build_filename (source_relpath, dent->d_name, NULL);


          if (!xdg_app_has_name_prefix (dent->d_name, required_prefix))
            {
              g_print ("Not exporting %s, wrong prefix\n", source_printable);
              continue;
            }

          g_print ("Exporting %s\n", source_printable);

          if (!glnx_file_copy_at (source_iter.fd, dent->d_name, &stbuf,
                                  destination_dfd, dent->d_name,
                                  GLNX_FILE_COPY_NOXATTRS,
                                  cancellable,
                                  error))
            return FALSE;
        }
      else
        {
          source_printable = g_build_filename (source_relpath, dent->d_name, NULL);
          g_print ("Not exporting non-regular file %s\n", source_printable);
        }
    }

  /* Try to remove the directory, as we don't want to export empty directories.
   * However, don't fail if the unlink fails due to the directory not being empty */
  do
    res = unlinkat (destination_parent_fd, destination_name, AT_REMOVEDIR);
  while (G_UNLIKELY (res == -1 && errno == EINTR));
  if (res == -1)
    {
      if (errno != ENOTEMPTY)
        {
          glnx_set_error_from_errno (error);
          return FALSE;
        }
    }

  return TRUE;
}