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Re: Structure layout in big/little endian modes
On Wednesday 23 of November 2011 19:33:01 ÐÐÐÐÐÐÐÑ ÐÐÐÑÐÐÐ wrote:
> Hello all!
>
> I have some lack of understanding how to write endianness independent
> definition of structure, which contains bit fields.
>
> For example, field, containing endpoint address in endpoint descriptor
> of USB device, can be defined as follow:
>
> struct EndpointAddress
> {
> UnsignedByte EndpointNumber: 4;
> UnsignedByte: 3;
> UnsignedByte TransferDirection: 1;
> };
>
> All USB descriptors have little endian byte order (and filling
> starting from least significant bit). If I would run some code which
> uses such definition on big endian CPU, I will get incorrect result.
some times ago i've established a nice c++ wrapper for byteorder conversion
and operation on bits/bytes ranges. please see for core source parts on
http://pluto.agmk.net/src/portable_bit_masking.tgz