/*
- * Copyright (C) 2006-2012 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2006-2013 Andre Noll <maan@systemlinux.org>
*
* Licensed under the GPL v2. For licencing details see COPYING.
*/
*
* If \a rfds is not \p NULL and the (non-blocking) file descriptor \a fd is
* not set in \a rfds, this function returns early without doing anything.
- * Otherwise The function tries to read up to \a sz bytes from \a fd. As for
- * xwrite(), EAGAIN is not considered an error condition. However, EOF
- * is.
+ * Otherwise The function tries to read up to \a sz bytes from \a fd, where \a
+ * sz is the sum of the lengths of all vectors in \a iov. As for xwrite(),
+ * \p EAGAIN is not considered an error condition. However, \p EOF is.
*
* \return Zero or a negative error code. If the underlying call to readv(2)
* returned zero (indicating an end of file condition) or failed for some
goto out;
}
*size = file_status.st_size;
+ /*
+ * If the file is empty, *size is zero and mmap() would return EINVAL
+ * (Invalid argument). This error is common enough to spend an extra
+ * error code which explicitly states the problem.
+ */
+ ret = -E_EMPTY;
+ if (*size == 0)
+ goto out;
+ /*
+ * If fd refers to a directory, mmap() returns ENODEV (No such device),
+ * at least on Linux. "Is a directory" seems to be more to the point.
+ */
+ ret = -ERRNO_TO_PARA_ERROR(EISDIR);
+ if (S_ISDIR(file_status.st_mode))
+ goto out;
+
ret = para_mmap(*size, mmap_prot, mmap_flags, fd, 0, map);
out:
if (ret < 0 || !fd_ptr)