merging the three forks of dfa.c ?

[Bruno Haible]

Hello Aharon, Tony,

There are now three variants of dfa.h and dfa.c in use in various GNU projects:
  - in GNU grep,
  - in GNU gawk,
  - in GNU gettext.
All of them have different bugs and different fixes applied.

Last week, while testing the GNU grep prerelease, I had to report fixes for
things that were already fixed in GNU gettext. Now I get a report about a
crash caused by a buffer overrun [1] that appears to be present in GNU grep
and GNU gettext, but fixed in GNU gawk. This is messy.

What can we do to remedy this? I propose to merge the three forks - they are
similar enough that a merge can be done in a couple of hours -, and then host
the "upstream" dfa.c in gnulib.

gnulib was created for the purpose of sharing common GNU source code. There
are now files shared between coreutils, tar, gettext, m4, diffutils, and many
other packages.

gettext would then get the latest copy of dfa.c through gnulib-tool. gawk and
grep, AFAICS, don't use gnulib-tool; for these packages the copy will have to
be manual.

So, what I offer and expect is:
  - I offer to do the merge this time now,
  - I (or the other gnulib maintainers) put in changes and fixes that you
    report (until you get gnulib git write access by yourself),
  - When you make changes to dfa.c in your projects, you notify gnulib about
    it.

How does that sound? Would you like to collaborate on this?

Bruno


[1] https://bugzilla.redhat.com/show_bug.cgi?id=483181