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Date:   Mon, 30 Jul 2018 06:31:30 -0300
From:   Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
To:     Pavel Machek <pavel@ucw.cz>
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Subject: Re: new libv4l2 (was Re: [PATCH, libv4l]: Make libv4l2 usable on
 devices with complex pipeline)
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Em Sat, 28 Jul 2018 23:11:10 +0200
Pavel Machek <pavel@ucw.cz> escreveu:

> Hi!
> 
> > > > Add support for opening multiple devices in v4l2_open(), and for
> > > > mapping controls between devices.
> > > > 
> > > > This is necessary for complex devices, such as Nokia N900.
> > > > 
> > > > Signed-off-by: Pavel Machek <pavel@ucw.cz>    
> > > 
> > > Ping?
> > > 
> > > There's a lot of work to do on libv4l2... timely patch handling would
> > > be nice.  
> > 
> > As we're be start working at the new library in order to support
> > complex cameras, and I don't want to prevent you keeping doing your
> > work, IMHO the best way to keep doing it would be to create two
> > libv4l2 forks:  
> 
> BTW.. new library. Was there decision what langauge to use? I know C
> is obvious choice, but while working on libv4l2, I wished it would be
> Rust...
> 
> Rewriting same routine over and over, with slightly different types
> was not too much fun, and it looked like textbook example for
> generics...

Whatever language it uses, the library should provide a standard C API
interface and avoid using libraries that may not be available on
the systems supported by the v4l-utils package, as other packages
and a libv4l-compatible interface should be linked using it.

It should also be something that the existing v4l-utils developers are
familiar with. Right now, we have only C and C++ code inside v4l-utils.

So, I'd say that the language should be either C (the obvious choice)
or C++.

It should also be licensed using the same terms as v4l-utils libraries,
e. g. LGPL 2.1+.

Thanks,
Mauro