diff-parseopt: correct variable types that are used by parseopt
authorNguyễn Thái Ngọc Duy <pclouds@gmail.com>
Wed, 29 May 2019 09:11:14 +0000 (16:11 +0700)
committerJunio C Hamano <gitster@pobox.com>
Wed, 29 May 2019 18:04:30 +0000 (11:04 -0700)
Most number-related OPT_ macros store the value in an 'int'
variable. Many of the variables in 'struct diff_options' have a
different type, but during the conversion to using parse_options() I
failed to notice and correct.

The problem was reported on s360x which is a big-endian
architechture. The variable to store '-w' option in this case is
xdl_opts, 'long' type, 8 bytes. But since parse_options() assumes
'int' (4 bytes), it will store bits in the wrong part of xdl_opts. The
problem was found on little-endian platforms because parse_options()
will accidentally store at the right part of xdl_opts.

There aren't much to say about the type change (except that 'int' for
xdl_opts should still be big enough, since Windows' long is the same
size as 'int' and nobody has complained so far). Some safety checks may
be implemented in the future to prevent class of bugs.

Reported-by: Todd Zullinger <tmz@pobox.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff.h
diff --git a/diff.h b/diff.h
index d9ad73f0e171e325240ff67f3351245547ca1858..7b66bf1b80c115620d22b4e8eacea0a4c0ea11d8 100644 (file)
--- a/diff.h
+++ b/diff.h
@@ -169,7 +169,7 @@ struct diff_options {
        const char *prefix;
        int prefix_length;
        const char *stat_sep;
-       long xdl_opts;
+       int xdl_opts;
 
        /* see Documentation/diff-options.txt */
        char **anchors;