[cocci] pcre vs pcre2

[cocci] pcre vs pcre2

[Richard W.M. Jones]

PCRE (not PCRE2) is end of life: http://www.pcre.org/

and may be removed from Fedora:

  https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org/message/K3BUC6T5VIG7LXOV4RVFO7IUPE2LGA2J/

It seems as if coccinelle has an optional dep on PCRE enabled/disabled
through ./configure --enable-pcre-syntax.  It's not entirely clear to
me what Fedora would lose by disabling this.

Does coccinelle plan to move to PCRE2?

I have moved a few projects over to PCRE2.  It's definitely not an
automatic conversion, although it also wasn't especially difficult.
Here's libguestfs.  This is mostly C and we maintain our own PCRE
bindings for OCaml which are not based on Markus Mottl's bindings, but
it should give you an idea of the changes:

  https://github.com/libguestfs/libguestfs/commit/82493579f38f39769861f31403ccfb8e97b41f96
  https://github.com/libguestfs/libguestfs-common/commit/0b244f2b0cfc920f2432f5df45e108583f0d2901

We decided not to support alternate PCRE or PCRE2 compiles since all
distros have provided PCRE2 for a long time.

Also:

  https://github.com/mmottl/pcre-ocaml/issues/25

Rich.

-- 
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Read my programming and virtualization blog: http://rwmj.wordpress.com
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Re: [cocci] pcre vs pcre2

[Julia Lawall]

On Fri, 22 Jul 2022, Richard W.M. Jones wrote:

> PCRE (not PCRE2) is end of life: http://www.pcre.org/
>
> and may be removed from Fedora:
>
>   https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org/message/K3BUC6T5VIG7LXOV4RVFO7IUPE2LGA2J/
>
> It seems as if coccinelle has an optional dep on PCRE enabled/disabled
> through ./configure --enable-pcre-syntax.  It's not entirely clear to
> me what Fedora would lose by disabling this.
>
> Does coccinelle plan to move to PCRE2?
>
> I have moved a few projects over to PCRE2.  It's definitely not an
> automatic conversion, although it also wasn't especially difficult.
> Here's libguestfs.  This is mostly C and we maintain our own PCRE
> bindings for OCaml which are not based on Markus Mottl's bindings, but
> it should give you an idea of the changes:
>
>   https://github.com/libguestfs/libguestfs/commit/82493579f38f39769861f31403ccfb8e97b41f96
>   https://github.com/libguestfs/libguestfs-common/commit/0b244f2b0cfc920f2432f5df45e108583f0d2901
>
> We decided not to support alternate PCRE or PCRE2 compiles since all
> distros have provided PCRE2 for a long time.
>
> Also:
>
>   https://github.com/mmottl/pcre-ocaml/issues/25

Thanks for the warning.  I don't think Coccinelle (the implementation)
actually uses PCRE in any important way.  It just makes PCRE availble to
the user for writing semantic patches.  I will look into how we can
convert (or at least make PCRE2 available as an additional option).

julia


>
> Rich.
>
> --
> Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
> Read my programming and virtualization blog: http://rwmj.wordpress.com
> nbdkit - Flexible, fast NBD server with plugins
> https://gitlab.com/nbdkit/nbdkit
>
>

Re: [cocci] pcre vs pcre2

[Markus Elfring]

> Does coccinelle plan to move to PCRE2?

I suggest to take another look at previous clarification requests.

Examples:
* Building the software for PCRE2 usage
  2018-07-17
  https://github.com/ggreer/the_silver_searcher/issues/1257

* Support for PCRE2
  2016-11-09
  https://github.com/mmottl/pcre-ocaml/issues/10

* Configuration possibilities for evaluation of regular expressions in SmPL constraints
  2018-11-20
  https://github.com/coccinelle/coccinelle/issues/149


How will development interests evolve further for involved software components?

Regards,
Markus

Re: [cocci] pcre vs pcre2

[Richard W.M. Jones]

On Fri, Jul 22, 2022 at 09:30:44PM +0200, Julia Lawall wrote:
> 
> 
> On Fri, 22 Jul 2022, Richard W.M. Jones wrote:
> 
> > PCRE (not PCRE2) is end of life: http://www.pcre.org/
> >
> > and may be removed from Fedora:
> >
> >   https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org/message/K3BUC6T5VIG7LXOV4RVFO7IUPE2LGA2J/
> >
> > It seems as if coccinelle has an optional dep on PCRE enabled/disabled
> > through ./configure --enable-pcre-syntax.  It's not entirely clear to
> > me what Fedora would lose by disabling this.
> >
> > Does coccinelle plan to move to PCRE2?
> >
> > I have moved a few projects over to PCRE2.  It's definitely not an
> > automatic conversion, although it also wasn't especially difficult.
> > Here's libguestfs.  This is mostly C and we maintain our own PCRE
> > bindings for OCaml which are not based on Markus Mottl's bindings, but
> > it should give you an idea of the changes:
> >
> >   https://github.com/libguestfs/libguestfs/commit/82493579f38f39769861f31403ccfb8e97b41f96
> >   https://github.com/libguestfs/libguestfs-common/commit/0b244f2b0cfc920f2432f5df45e108583f0d2901
> >
> > We decided not to support alternate PCRE or PCRE2 compiles since all
> > distros have provided PCRE2 for a long time.
> >
> > Also:
> >
> >   https://github.com/mmottl/pcre-ocaml/issues/25
> 
> Thanks for the warning.  I don't think Coccinelle (the implementation)
> actually uses PCRE in any important way.  It just makes PCRE availble to
> the user for writing semantic patches.  I will look into how we can
> convert (or at least make PCRE2 available as an additional option).
> 
> julia

To follow up, here's the Fedora bug:

https://bugzilla.redhat.com/show_bug.cgi?id=2128281

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
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