Perl's ExtUtils::MakeMaker fails and proposed fix

[Marco Moreno]

On Mon, Jul 11, 2011 at 9:00 AM, Reini Urban wrote:
>
> 2011/7/11 Reini Urban:
> > 2011/7/7 Marco Moreno:
> >> After doing a little debugging, I discovered why installing ExtUtils::MakeMaker
> >> was failing for me.  ExtUtils::MM_Cygwin.pm contains:
> >>
> >> =item maybe_command
> >>
> >> If our path begins with F</cygdrive/> then we use C<ExtUtils::MM_Win32>
> >> to determine if it may be a command.  Otherwise we use the tests
> >> from C<ExtUtils::MM_Unix>.
> >>
> >> =cut
> >>
> >> sub maybe_command {
> >>    my ($self, $file) = @_;
> >>
> >>    if ($file =~ m{^/cygdrive/}i) {
> >>        return ExtUtils::MM_Win32->maybe_command($file);
> >>    }
> >>
> >>    return $self->SUPER::maybe_command($file);
> >> }
> >>
> >>
> >> Obviously, if your cygdrive prefix is something else (e.g. '/'), then
> >> this will fail.
> >>
> >> What do you think of this instead:
> >>
> >> =item maybe_command
> >>
> >> Determine whether a file is native to Cygwin by checking whether it
> >> resides inside the Cygwin installation (using Windows paths).  If so,
> >> use C<ExtUtils::MM_Unix> to determine if it may be a command.
> >> Otherwise use the tests from C<ExtUtils::MM_Win32>.
> >>
> >> =cut
> >>
> >> sub maybe_command {
> >>    my ($self, $file) = @_;
> >>
> >>    my $cygwin_winpath = Cygwin::posix_to_win_path('/', 1);
> >>    my $file_winpath = Cygwin::posix_to_win_path($file, 1);
> >>
> >>    return ($file_winpath =~ /^${cygwin_winpath}/)
> >>        ? $self->SUPER::maybe_command($file)
> >>        : ExtUtils::MM_Win32->maybe_command($file);
> >> }
>
> I improved it a bit, because I don't like userdata end up in regexp.
>
>    my $cygpath = Cygwin::posix_to_win_path('/', 1);
>    my $filepath = Cygwin::posix_to_win_path($file, 1);
>
>    return (substr($filepath,0,length($cygpath)) eq $cygpath)
>        ? $self->SUPER::maybe_command($file)        # Unix
>        : ExtUtils::MM_Win32->maybe_command($file); # Win32
>
>
> >>
> >>
> >> This passed all the tests and installed ok for me.  Does this look
> >> ok to you and is it reasonable to assume that native Cygwin
> >> commands will always be inside the Cygwin installation directory?
> >> If this proposed change is worthy of implementing, what is the best
> >> way to do it?  rt.cpan.org?
> >
> > Sorry, I did not come to test this this weekend.
> >
> > Yes, this uncommon cornercase looks worthy to be fixed.
> > Please file a perlbug for this. It should go to rt.perl.org.
>
> I just added it as https://rt.perl.org/rt3/Ticket/Display.html?id=94532


Reini,

This bug from last year just bit me again today.  I checked the
perlbug you submitted and its status says it was rejected.  Do you
know why?  Should it be resubmitted?

Marco Moreno

--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple