From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gleb Natapov <gleb@redhat.com>
Subject: Re: [PATCH kvm-unit-tests 2/4] Introduce a C++ wrapper for the kvm
 APIs
Date: Wed, 24 Nov 2010 19:16:46 +0200
Message-ID: <20101124171646.GH20014@redhat.com>
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Cc: Jes Sorensen <Jes.Sorensen@redhat.com>,
	Anthony Liguori <anthony@codemonkey.ws>,
	Alexander Graf <agraf@suse.de>,
	Marcelo Tosatti <mtosatti@redhat.com>, kvm@vger.kernel.org
To: Avi Kivity <avi@redhat.com>
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On Wed, Nov 24, 2010 at 07:01:00PM +0200, Avi Kivity wrote:
> On 11/24/2010 06:55 PM, Gleb Natapov wrote:
> >>  >
> >>  >What you did above is making the exact same mistake as is done with the
> >>  >current i440fx.c code.
> >>
> >>  If a real life 440fx has an i8042, then an emulated 440fx should
> >>  have an emulated i8042.  It's not complicated.
> >>
> >Correct. But it can be achieved by making 440fx a class that includes
> >other classes or by building it from different classes linked through
> >common interfaces.
> 
> Both are fine, and not in conflict with the example that started this.
> 
> If the i8042 is completely stock, we write
> 
> class i440fx {
> private:
>     i8042 kbc;
> }
> 
> (or the C equivalent)
> 
> If it's not completely stock, we substitute some subclass that takes
> care of the differences.
> 
And if you want to connect ISA sound blaster to that you make subclass
with SB device? No. You make ISA bus functionality available from i440fx
and connect SB there. So now you have bunch of devices that are part of
i440fx class and others that are connected via ISA bus functionality and
all that because you read to deeply into PIIX3 spec?
 
--
			Gleb.