[linux-audio-user] [PATCH] oss2jack for kernel => 2.6.17 (with patch)

[Dmitry Baikov]

I wrote about the same thing to FUSE maintainer, below is the reply.
Since I don't have enough time, I dropped the idea.
But it's still a cool project to do :)


Regards,
Dmitry.

-----------------------
From: Miklos Szeredi <miklos at szeredi.hu>

> Oss2jack project -
> http://fort.xdas.com/~kor/oss2jack/ - uses FUSD - Framework for
> User-Space Drivers, which is unmaintained and doesn't seem to go in
> the kernel anytime soon.
>
> So, FUSE is in the kernel already and implements more generic
> functionality than FUSD. I think it is natural to extend FUSE a bit to
> implement user-space devices.
> The only things it lacks are:
> 1) ioctl support - seems not hard to add

It's not easy.  The basic problem is that ioctl arguments are not well
defined size and structure, and decoding/encoding them does not belong
in FUSE.

It would theoretically be possible to do the decoding/encoding in the
userspace filesystem, but I don't yet see how that can be done nicely.

> 2) mmap support, i.e. ability to share a buffer with user app - can't
> estimate the difficulty.

I can't either.  It involves VM trickery, which is not an easy
subject.

> I'm willing to help adding this functionality or add it myself and
> will appreciate a guidance.

I'd rather not get involved in the coding part, at least until I see
where this is heading.  But I'm happy to answer any questions.