[FFmpeg-devel] [RFC] print license and configuration for each lib

[Diego Biurrun]

On Fri, Oct 30, 2009 at 06:53:39PM +0000, M?ns Rullg?rd wrote:
> Diego Biurrun <diego at biurrun.de> writes:
> 
> > On Wed, Oct 28, 2009 at 06:59:11PM +0000, M?ns Rullg?rd wrote:
> >> Diego Biurrun <diego at biurrun.de> writes:
> >> 
> >> > Here's something I started and wanted to have some feedback on before I
> >> > progress.  Sometimes it can be useful to have the exact configuration
> >> > and license string in each library and have it printed by each library.
> >> >
> >> > Here is a proof of concept patch that does it for libavutil and
> >> > libavcodec.  Once the chinks are worked out I can lather, rinse, repeat
> >> > for the others.
> >> >
> >> > I made two alternative implementations, choose the one you prefer.
> >> > Things that could possibly be improved (but might not be worth the
> >> > trouble):
> >> >
> >> > - The licensing information for each library could be more detailed.
> >> >   For example, libavutil is always LGPL, even when FFmpeg was compiled
> >> >   in GPL mode.
> >> > - Use a single function to perform the job.
> >> >
> >> > +void avutil_license(void)
> >> > +{
> >> > +    const char* libavutil_license = "libavutil license: "FFMPEG_LICENSE;
> >> > +    av_log(NULL, AV_LOG_INFO, "%s\n", libavutil_license);
> >> > +}
> >> 
> >> Returning the string would probably be more flexible.
> >
> > Like I have done in $attached for libavcodec?  Anything else?
> >
> > +const char* avcodec_license(void)
> > +{
> > +    return "libavcodec license: " FFMPEG_LICENSE "\n";
> > +}
> 
> Drop the "libfoo thing:" prefixes.  Whatever is using the string can
> add those in a way that makes sense in its context.

I agree that this would likely be more flexible, but note that I have a
vested interest in seeing this exact string appear in the lib binary :)

Diego