Re: [musl] Re: [QUESTION] Which fnmatch() functionality does elfutils depend on?

[Max Rees <maxcrees@me.com>]

On Mon Oct 26 01:28 PM, Érico Nogueira wrote:
> On Mon Oct 26, 2020 at 3:10 PM -03, Mark Wielaard wrote:
> > Hi Érico,
> >
> > On Mon, 2020-10-26 at 12:03 -0300, Érico Nogueira via Elfutils-devel
> > wrote:
> > > Do elfutils program actually depend on the extra functionality
> > > enabled by
> > > FNM_EXTMATCH? Is changing the flag to have no effect a "bug"?
> >
> > Yes. The extended wildcard pattern is relied upon by both
> > eu-strip with
> >
> > --keep-section=SECTION Keep the named section. SECTION is an
> > extended wildcard pattern. May be given
> > more than once.
> >
> > and eu-elfcompress with
> >
> > -n, --name=SECTION SECTION name to (de)compress, SECTION is an
> > extended wildcard pattern (defaults to
> > '.?(z)debug*')
> >
> > In the eu-strip case it might be reasoned that instead of a
> > wildcard pattern the user might most of the time simply provide
> > a section name as is (especially since the option may be given
> > multiple times). But in the case of eu-elfcompress the
> > program relies on the default SECTION name being an extended
> > wildcard pattern. So not supporting FNM_EXTMATCH breaks the
> > default functionality of eu-elfcompress.
> >
> > Cheers,
> >
> > Mark
> 
> Understood, thank you. I'm replying to the musl mailing list as well,
> then, to hopefully gather more opinions, since I don't know what the
> best way of solving this would be.
> 
> Thanks,
> Érico

When I was working on porting elfutils to Adélie (kind of on the
backburner right now) I noticed this problem as well. Rather than try to
add FNM_EXTMATCH support to musl, I worked around it in elfutils in this
manner.

1. I changed the default like so:

- add_pattern (".?(z)debug*");
+ add_pattern (".debug*");
+ add_pattern (".zdebug*");

2. I updated the corresponding help text to mention this new default.

The user could do something similar themselves with multiple "-n"
options.

Max