[Xcb] Alignment problems in XKB GetGeometry

[Ran Benita]

I've been wanting to test XKB's GetGeometry request. However I've hit an
impasse before I got to the interesting parts (some test code attached).

First there a difference between the XKB spec and Xlib / X server. The
spec says:
http://www.x.org/releases/X11R7.7/doc/kbproto/xkbproto.html#appD::Requests

1     CARD8          opcode
1     19          xkb-opcode
[...]
2     p          nProperties
[...]
f     KB_COUNTED_STRING16          labelFont
8p     LISTofKB_PROPERTY          properties
[...]

KB_PROPERTY     4+n+v
2     n          nameLength
n     STRING8          name
2     v          valueLength
v     STRING8          value

Which implies (AFAIK) that there is no padding. This is what xkb.xml
has.
However the X server has:
http://cgit.freedesktop.org/xorg/xserver/tree/xkb/xkb.c?id=b6e5c4669e0db391966deb397e8c975ec7f0124d#n4406

XkbWriteGeomProperties(char *wire, XkbGeometryPtr geom, Bool swap)
[...]
        wire = XkbWriteCountedString(wire, prop->name, swap);
        wire = XkbWriteCountedString(wire, prop->value, swap);
[...]

Which implies there *is* padding between and after name and value
(aligning n+2 to 4 bytes). This is implemented in xkb.xml as
CountedString16.

Now if I try to change xkb.xml to read simply:

	<struct name="Property">
		<field name="name" type="CountedString16" />
		<field name="value" type="CountedString16" />
	</struct>

Then struct xcb_xkb_property_t is empty, which is undefined behavior
(AFAIK) and doesn't work anyway (the padding calculations becomes
confused). If I try to inline the CountedString16 definition into
Property, it doesn't work either.

Are there any suggestions on how I might proceed?

Thanks,
Ran
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