[FFmpeg-devel] [PATCH 02/21] avcodec/zlib_wrapper: Add wrappers for zlib inflateInit, inflateEnd

[Tomas Härdin]

ons 2022-03-16 klockan 20:32 +0100 skrev Andreas Rheinhardt:
> Tomas Härdin:
> > > +int ff_inflate_init(FFZStream *z, void *logctx)
> > > +{
> > > +    z_stream *const zstream = &z->zstream;
> > > +    int zret;
> > > +
> > > +    z->inited = 0;
> > > +    zstream->next_in  = Z_NULL;
> > > +    zstream->avail_in = 0;
> > > +    zstream->zalloc   = Z_NULL;
> > > +    zstream->zfree    = Z_NULL;
> > > +    zstream->opaque   = Z_NULL;
> > 
> > why not bzero()?
> > 
> > Rest of the patch looks fine
> > 
> 
> bzero()? You mean memset to zero? The reason that I initialize
> exactly
> these fields is because these are exactly the fields required to be
> initialized by zlib (for inflate; next_in and avail_in are not
> required
> to be initialized for deflate): "The fields next_in, avail_in,
> zalloc,
> zfree and opaque must be initialized before by the caller." zlib
> treats
> all the other fields as uninitialized, so why should we initialize
> them
> (Actually reinitialize them -- most FFZStreams are already zeroed
> initially as part of a codec's private context.)? The way it is done
> in
> this patch shows directly which elements zlib expects to be set;
> setting
> everything would not achieve the same.

Right. Looks OK then

/Tomas