Re: [PATCH] printf: Enable grouping decimal values

[Jeff Johnston <jjohnstn at redhat dot com>]

On 04/02/10 03:21 PM, Corinna Vinschen wrote:
> On Feb  4 21:12, Corinna Vinschen wrote:
> > On Feb  4 13:30, Jeff Johnston wrote:
> > > On 01/02/10 03:47 PM, Corinna Vinschen wrote:
> > > > Hi,
> > > >
> > > > the below patch is derived from NetBSD code.  It enables printf/wprintf
> > > > grouping using the thousands' grouping character from the locale
> > > > information when the ' (single quote) flag character has been specified
> > > > in decimal conversions (i, d, u, f, F, g, G), as specified by POSIX-1.2008.
> > >
> > > This is a tough patch to review because of all the format changes
> > > and ifdefs in the patch itself.
> > >
> > > I did notice one spot where the size is being calculated and the
> > > grouping ptr is moved to do this calculation.  I can't see anywhere
> > > where you are resetting grouping before the output is written.  This
> > > seems like a mistake, but perhaps I am missing something.
> >
> > That's correct.  In case of float values there are two runs, one to
> > compute the size, the number of lead digits, the number of required
> > separators and and the number of repetitions for the leftmost grouping.
> > While doing that, the grouping pointer is moved to the end of the
> > grouping string:
> > [...]
> > Later, when the float value is actually printed, the grouping pointer
> > moves backward again, depending on the number of repetitions and
> > actual number of explicit groupings:
> > [...]
>
> One more point: Consider that the grouping string defines the grouping
> from right to left, while the printing goes from left to right.  That
> should explain why moving the grouping pointer backwards while printing
> makes sense.

Ah, that makes sense regarding why you were counting repetitions.  Ok 
then to commit.

-- Jeff J.