Apache2::Reload problem (ModPerl::Util bug)

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In 2.0.0, if there are heirarchical packages, and Apache2::Reload is
configured to reload the 'parent', it blows away the 'children' package
namespaces (and doesn't reload the children.)  For example, if @INC has:

Fubar.pm
Fubar/Child.pm

And Apache2::Reload reloads package Fubar, it blows away
Fubar::Child::* and only reloads file Fubar.pm.   Only a server
restart can recover from this point.

The actual unloading work is done by ModPerl::Util::unload_package(),
whose behavior is contrary to the docs, which say:

   "unload_package()" takes care to leave sub-stashes intact while
   deleting the requested stash. So for example if "CGI" and "CGI::Carp"
   are loaded, calling "unload_package('CGI')" won't affect "CGI::Carp".


I only partly understand how unload_package() works, but it seems to
just iterate over symbols in the package and blow them away, without
regard for the actual file from which the symbol was instantiated.

I tried modifying the code to skip over symbols that correspond
to a key in %INC, which seems logical and works correctly in my tests,
but may not be a complete or perfect solution for reasons beyond
my current testing/thinking.  However, in my tests, it works correctly
if either the parent package, child package, or both are modified.

Comments/suggestions about the correctness of this patch requested.

Thanks.


*** ./blib/lib/ModPerl/Util.pm  2005-05-22 10:14:19.000000000 -0700
--- /usr/lib/perl5/site_perl/5.8.5/i686-linux/ModPerl/Util.pm   2005-05-29 10:09:02.000000000 -0700
***************
*** 36,55 ****
--- 36,58 ----
   sub unload_package_pp {
       my $package = shift;
       no strict 'refs';
       my $tab = \%{ $package . '::' };

       # below we assign to a symbol first before undef'ing it, to avoid
       # nuking aliases. If we undef directly we may undef not only the
       # alias but the original function as well

       for (keys %$tab) {
+         if (my ($subpackage) = /(.*)::/) {
+             next if exists $INC{"$package/$subpackage.pm"};
+         }
           my $fullname = join '::', $package, $_;
           # code/hash/array/scalar might be imported make sure the gv
           # does not point elsewhere before undefing each
           if (%$fullname) {
               *{$fullname} = {};
               undef %$fullname;
           }
           if (@$fullname) {
               *{$fullname} = [];
               undef @$fullname;