in reply to Mixing C and perl

Instead of accessing the hash through a method on the Perl side, you can just use it as the perl wrapper for the C object.

You will have to store the C pointer inside the hash, for instance as $hash{__c_ptr}. Another option is to use <c>~ magic to save it, that way it will be invisible from the Perl side.

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Re^2: Mixing C and perl
by jpl (Monk) on Jan 17, 2012 at 18:51 UTC
    I want to be able to get directly to the XS methods using 
    $amd->method();

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    If $amd is just a blessed hash reference, I think I'd have to "indirect through" the perl wrapper: 
    # In AddrMatch.pm
sub method {
    my $self = shift;
    my $Cptr = $self->{__c_ptr};
    return $Cptr->xs_method();
}

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    Also not too onerous. But will h2xs do all the right stuff to do the dynamic linking? I confess to considerable uncertainty about how the linking is made to work. I have tested the original model, and it appears to be doing the right thing with linking and reference counts.
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      In the Perl-hash-wraps-C-struct setup, an object looks like {foo => 'bar', ... '__cptr' => \2131231231}. Well, with- or without the scalar reference to the number-that-is-a-pointer

      What you can do to make the XS methods work appropriately on this construct while being able to store stuff regularly from Perl as well, is to define a typemap that will a) check it got a hashref b) check that the class inherits from your package, c) fetch the __cptr slot of your hash-object, d) check it's a scalar ref, e) use the integer as a pointer, f) cast that into your C type. b), d), e), f) are done in T_PTROBJ already. This would allow you to write XS like with T_PTROBJ. The only downside is that you'd lose the ability to access the outer hash from XS.

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        The only downside is that you'd lose the ability to access the outer hash from XSM

        Not really, just keep a pointer to the wrapping hash also inside the C structure, as in the OP sample code.

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