[FFmpeg-devel] [RFC] WC3 decoder without AVPaletteControl

[Reimar Döffinger]

I'll try once more to fix the palette issues...

On Wed, Apr 15, 2009 at 08:47:24PM +0200, Michael Niedermayer wrote:
> On Wed, Apr 15, 2009 at 05:29:14PM +0200, Reimar D?ffinger wrote:
> > On Wed, Apr 15, 2009 at 04:17:24PM +0200, Michael Niedermayer wrote:
> > > On Sun, Apr 12, 2009 at 01:26:33PM +0200, Reimar D?ffinger wrote:
> > > > +int av_grow_packet(AVPacket *pkt, int grow_by)
> > > > +{
> > > > +    void *new_ptr;
> > > 
> > > > +    if (!grow_by)
> > > > +        return 0;
> > > 
> > > for what is that good for?
> > 
> > Avoiding a pointless realloc in case someone does something stupid like
> > av_grow_packet(pkt, 0);
> 
> people should not do such stupid things
> 
> 
> > 
> > > > +    if (pkt->size + FF_INPUT_BUFFER_PADDING_SIZE > INT_MAX - grow_by)
> > > > +        return -1;
> > > 
> > > could you write this in a way that is free of overflows please ;)
> > 
> > Hm. Bad "documentation", I hadn't decided what grow_by < 0 is supposed to
> > mean or if I should just make it unsigned (the latter I admit would not
> > help here).
> > So
> 
> > > if (grow_by < 0 || pkt->size + FF_INPUT_BUFFER_PADDING_SIZE > INT_MAX - grow_by)
> > good enough?
> > I also assumed that pkt->size + FF_INPUT_BUFFER_PADDING_SIZE would not
> > overflow since the allocated buffer must already be that big, if you
> > dislike that.
> 
> maybe
> 
>    (unsigned)grow_by > INT_MAX - FF_INPUT_BUFFER_PADDING_SIZE 
> || pkt->size > INT_MAX - FF_INPUT_BUFFER_PADDING_SIZE - grow_by 
> 
> ?
> 
> > > > Index: libavformat/utils.c
> > > > ===================================================================
> > > > --- libavformat/utils.c	(revision 18467)
> > > > +++ libavformat/utils.c	(working copy)
> > > > @@ -277,6 +277,20 @@
> > > >      return ret;
> > > >  }
> > > >  
> > > > +int av_append_packet(ByteIOContext *s, AVPacket *pkt, int size)
> > > > +{
> > > > +    int ret;
> > > > +    int old_size;
> > > > +    if (!pkt->size)
> > > > +        return av_get_packet(s, pkt, size);
> > > > +    old_size = pkt->size;
> > > > +    ret = av_grow_packet(pkt, size);
> > > 
> > > isnt av_grow_packet already checking for pkt->size==0 ?
> > 
> > Yes, but it only allocates a new packet then. av_get_packet also sets
> > pkt->pos. Sure, maybe a bit overkill for a single assignment, just
> > thought it might be more future-proof.
> 
> well, fine leave that then

One more try...
-------------- next part --------------
A non-text attachment was scrubbed...
Name: wc3_pal.diff
Type: text/x-diff
Size: 15832 bytes
Desc: not available
URL: <http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/attachments/20101118/1555a37c/attachment.diff>