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

Mark Kettenis mark.kettenis at xs4all.nl
Thu Jul 9 02:54:38 PDT 2009


> Date: Thu, 9 Jul 2009 19:53:17 +1000
> From: Peter Hutterer <peter.hutterer at who-t.net>
> 
> 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.

Seomthing with int16, int32, int64?


More information about the xorg-devel mailing list