According to the Linux open(2) man page, open() must return EISDIR
if a directory was attempted to be opened for writing. Our emulation
in mingw_open() does not get this right: it checks only for O_CREAT.
Fix it to check for a write request.
This fixes a failure in reflog handling, which opens files with
O_APPEND|O_WRONLY, but without O_CREAT, and expects EISDIR when the
named file happens to be a directory.
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
ba6fad02b6