Re: sscanf: implement basic character sets

From: Andrew Morton
Date: Mon Mar 07 2016 - 18:24:41 EST


On Mon, 7 Mar 2016 18:12:20 -0500 Jessica Yu <jeyu@xxxxxxxxxx> wrote:

> +++ Jessica Yu [26/02/16 15:28 -0500]:
> >+++ Jessica Yu [26/02/16 15:20 -0500]:
> >>Implement basic character sets for the '%[' conversion specifier.
> >>
> >>The '%[' conversion specifier matches a nonempty sequence of characters
> >>from the specified set of accepted (or with '^', rejected) characters
> >>between the brackets. The substring matched is to be made up of characters
> >>in (or not in) the set. This is useful for matching substrings that are
> >>delimited by something other than spaces.
> >>
> >>This implementation differs from its glibc counterpart in the following ways:
> >>(1) No support for character ranges (e.g., 'a-z' or '0-9')
> >>(2) The hyphen '-' is not a special character
> >>(3) The closing bracket ']' cannot be matched
> >>(4) No support (yet) for discarding matching input ('%*[')
> >>
> >>Signed-off-by: Jessica Yu <jeyu@xxxxxxxxxx>
> >
> >Since this version is largely based on Rasmus' sample bitmap code
> >(with only very minor tweaks), what is the best way to provide
> >attribution in this case? A Suggested-by: tag or another
> >Signed-off-by: tag (since actual code is involved)?
>
> Andrew, friendly ping on this patch and question? :-)

Rasmus's Signed-off-by: would be most appropriate, please.

I've queued the patch for some testing, however the changelog which
used to have IMO-inadequate justification now has no justification at
all!

So please send along a paragraph or two which we can put in there to
explain to people why we believe this change should be made to the
kernel. Thanks.