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

[Måns Rullgård]

Diego Biurrun <diego at biurrun.de> writes:

> On Fri, Oct 30, 2009 at 07:20:38PM +0100, Stefano Sabatini wrote:
>> On date Friday 2009-10-30 18:51:23 +0100, Diego Biurrun encoded:
>> > 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_configuration(void)
>> > > > +{
>> > > > +    const char* configuration = "libavutil configuration: " FFMPEG_CONFIGURATION;
>> > > > +    av_log(NULL, AV_LOG_INFO, "%s\n", configuration);
>> > > > +}
>> > > > +
>> > > > +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?
>> > 
>> > --- libavcodec/avcodec.h	(Revision 20419)
>> > +++ libavcodec/avcodec.h	(Arbeitskopie)
>> > @@ -3062,6 +3062,16 @@
>> >  unsigned avcodec_version(void);
>> >  
>> >  /**
>> > + * Prints the libavcodec build-time configuration.
>> > + */
>> > +const char* avcodec_configuration(void);
>> 
>> Nit: "const char* " -> "const char *", here and below.
>
> Hmm, any particular reason why?

1. That's how we always do it.
2. It is consistent with how variables should be declared.
3. Variables should be declared like that because a declaration like
   "int *a, b;" declares one pointer and one int, not two pointers.
4. It looks nicer.

-- 
M?ns Rullg?rd
mans at mansr.com