Re: [PATCH 3/4] Modify obex_write_stream logic

[Vinicius Costa Gomes <vinicius.gomes@openbossa.org>]

Hi Luiz,

On 11:27 Thu 16 Jun, Luiz Augusto von Dentz wrote:
> Hi,
> 
> On Wed, Jun 15, 2011 at 5:59 PM, Slawomir Bochenski <lkslawek@gmail.com> wrote:
> >
> > The loop is only used before we start streaming. That is because if
> > there was no streaming started, request will be finished after
> > returning from OpenOBEX callback. To still allow plugins to use the
> > original approach, the loop guarantees that there will be another
> > read() if the service plugin did not explicitly returned -EAGAIN, so
> > read() still decides explicitly when it wants the suspending to
> > happen, therefore it is perfectly aware of when to call
> > obex_object_set_io_flags().
> >
> > This is just how OpenOBEX works - unless we are streaming body
> > headers, we should add headers when getting event and suspend if we
> > want to postpone finishing the request. I would not call this loop
> > "dangerous".
> 
> I would say this is not a limitation of OpenOBEX, just the way we
> implement async io in obexd.
> 
> > Well, we have also another possible header types and generally in some
> > near future a profile may need to use more than just application
> > parameters header and/or body headers (e.g. user defined headers).
> > This might also allow sending Length header asynchronously (which by
> > quick looking at code is not possible now).
> >
> > With approach I presented the cost of changes is very low and
> > additionally makes it extremely easy to return all possible headers.
> > Also everything just works, together with support for asynchronous
> > I/O.
> >
> > Adding additional callback will unnecessarily complicate the code.
> 
> Sorry I have to disagree here, adding another callback probably
> simplify the code a bit since we can have something like this:
> 
> if (!streaming && driver->get_apparams)
>     driver->get_apparams...
> 
> So just drivers that support get_apparams will be called and that
> should be enough to guarantee the apparams are added in the beginning
> packet.
> 
> Custom headers are a different matter, right now we don't have any
> plugin/driver who need them.

But we will have soon, BIP needs them. So we better start considering
how should we export it to the plugins.

> 
> -- 
> Luiz Augusto von Dentz
> --
> To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html


Cheers,
-- 
Vinicius