[perl #48419] Safe and use encoding 'utf8'

[Ville Luolajan-Mikkola]

# New Ticket Created by "Ville Luolajan-Mikkola"
# Please include the string: [perl #48419]
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Hi,

I have already submitted this bug on CPAN also, but I suppose this is
the right place?

I have found that Safe does not work (at all) if I "use encoding
'utf8';". All I get is an error message:

Can't locate object method "renewed" via package "Encode::utf8"
(perhaps you forgot to load "Encode::utf8"?) at (eval 2) line 1.

As far as I know, there is no Encode::utf8 (it's supposed to be
internal), and commenting out that "use encoding 'utf8';" makes the
same source not die anymore.

I use perl 5.8.8 with its included Safe.pm 2.12, but have also tried
using the 2.11 from CPAN instead. I have tested it on the default perl
included on Debian 4.0, on one compiled from vanilla source, and the
one bundled with Mac OS X 10.5.1. The result is always the same.

There is a workaround to the problem, however, I don't really
understand how or why this works. :) In reval() inside Safe.pm; just
after the $evalsub has been retrieved from lexless_anon_sub(), if I
append anything (even an empty string) to the $expr, the problem
disappears!

In code:

my $evalsub = lexless_anon_sub($root,$strict, $expr);
$expr."";
return Opcode::_safe_call_sv($root, $obj->{Mask}, $evalsub);

Sample script for demonstration:
-----
#!/usr/bin/perl

use encoding 'utf8';
use Safe;

sub foo {
my $expr = shift();
if (my $safe = new Safe()) {
$ret = $safe->reval ("$expr");
}
if ($@) {
print "Error while evaluating \"$expr\": $@\n";
}
}

&foo('print "eval OK\n";');
-----

A fix to this problem would be much appreciated, as the workaround is
flaky at best...

Cheers,

--
- Ville

[Rafael Garcia-Suarez]

The real workaround would be to permit the called method to be
imported in the Safe compartment. That is, once $safe is created, and
before the call to reval(), do:

$safe->share('Encode::Encoding::renewed');

I'm not sure that bug can be safely fixed in Safe.