[PATCH 01/18] include: introduce byte counting functions.

David Jander david.jander at protonic.nl
Thu Jul 9 03:54:07 PDT 2009


On Thursday 09 July 2009 11:55:11 René Rebe wrote:
> Peter Hutterer wrote:
> > On Thu, Jul 09, 2009 at 11:01:54AM +0200, David Jander wrote:
> >> On Thursday 09 July 2009 02:04:59 Peter Hutterer wrote:
> >>> This patch adds the following three functions:
> >>>  num_bytes_for_bits(bits) - the number of bytes needed to hold 'bits'
> >>>  num_dwords_for_bytes(bytes) - the number of 4-byte units to hold
> >>> 'bytes' pad_to_dwords(bytes) - the closest multiple of 4 equal to or
> >>> larger than 'bytes'.
> >>
> >> Sorry to make this probably useless comment about naming, but while a
> >> byte has a defined length (8 bits), the meaning of "word" and "dword" in
> >> terms of length is undefined. By definition "word" in computing means
> >> the natural unit of data used by a particular computer design. This
> >> would be 32 bits on most 32-bit computers, and by consequence a "dword"
> >> would be 64 bit wide. Your definition of the names "word" and "dword"
> >> seem to be 16-bit platform-specific... not the most common platform for
> >> Xorg!
> >> Please, let's deprecate this flawed naming convention, and not use it in
> >> new code... it's confusing and just plain wrong when used on
> >> platform-independent code!
> >
> > This can be changed with a simple search+replace, I wouldn't mind
> > changing it.
> >
> > Please suggest a better alternative naming though, the only appropriate
> > equivalent I can think of is num_4byte_units_for_bytes and similar which
> > does make the function names a tad long.
>
> ...int8..., ...int16..., ...int32..., ...

I agree. Although in theory 'int8' and 'byte' are of the same length (not 
necessarily same type).

If you want to make the names _really_ short, you might consider the 
convention used in the linux kernel and some other places: u8, s8, u16, s16, 
u32.... etc, very short and still readable ;-)

Thanks!

Best regards,

-- 
David Jander
Protonic Holland.


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