[Ffmpeg-devel] Patch for dynamic liba52.so loading

Måns Rullgård mru
Sat Jun 11 11:28:37 CEST 2005

Rich Felker <dalias at aerifal.cx> writes:

> On Fri, Jun 10, 2005 at 06:44:47PM +0200, August Mayer wrote:
>> Hello,
>> It seems that the code for dynamically loading liba52.so (CONFIG_AC3 && 
>> CONFIG_A52BIN) has been rotting for some time. There are two problems in 
>> libavcodec/a52dec.c:
>> 1. It uses fprintf instead of av_log, and
>> 2. libavcodec/parser.c directly links to a52_syncinfo, which is not 
>> available as a global symbol in this case.
>> I've corrected these two problems; attached are the patches for it.
>> Moreover, I have changed the code so that the references and
>> function pointers are stored in static variables instead of the
>> AVCodecContext. This looks more sensible to me, because liba52 only
>> needs to be loaded once during program lifetime. Is it possible
>> that there are multiple codec contexts? If so, then liba52.so would
>> have been loaded multiple times.
> Of course there are multiple codec contexts. Is there a good reason
> for dynamic loading support? IMO it's unnecessary complexity that
> should just be removed..

There is no technical reason for dynamic loading.  It allows
libavcodec to be distributed under the LGPL, and still use liba52,
even if you believe the lies being perpetrated by the FSF.

M?ns Rullg?rd
mru at inprovide.com

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