PATCH: ppc fix 2
gmturner007 at ameritech.net
Wed Oct 30 10:13:36 CST 2002
On Wednesday 30 October 2002 07:22 am, Marcus Meissner wrote:
> Fixed LITTLE_ENDIAN_32_READ macro to at least compile.
btw, this seems to imply that even with the parentheses fix, it's still
not right... is that the case? You seem like somebody who's up on PPC
issues. Note that this is only intended to support UINT32's (I'll make
that clearer by changing the macro names in an upcoming patch).
There is another issue with the DataRepresentation stuff that I didn't
think of until this morning. NDR allows several different modes in
terms of endianness, float representation, signed int representation,
etc. MS takes advantage of this by having different "native" data
representations, based on the platform. Looking at the Platform SDK
rpcndr.h, for example, PPC gets big-endian, i386 gets little-endian.
Then, it seems, they implement their marshall/unmarshall code in terms
of these "native" representations. I'm deducing this from the
MIDL-generated stub code; that code compares the DataRepresentation
coming off the wire to the native DataRepresentation; if there's a
mismatch, it converts before calling the unmarshall code (currently the
conversion functions are unimplemented in wine).
What this all means, I think, is that my implementation is wrong for
non-i386 platforms. I was hard-coding the native data representation
to little-endian (the i386 way). This will work for i386, but for
other platforms, it will break against precompiled binaries, because
the assumed native data representation is compiled right in to the
executable via #define's. To fix, I think I need to have per-platform
native DataRepresentations like microsoft, and change the
marshall/unmarshall code to use it.
Anyhow, just thinking aloud there, and, I guess, hoping that if I'm
getting this all wrong, someone will correct me. My original question
is the main one: are the semantics of my macro's wrong, or just the
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