[FFmpeg-devel] [PATCH 1/7] avutil: add FF_BAIL_ON_OVERFLOW

[wm4]

On Fri, 16 Dec 2016 13:36:09 +0700
Muhammad Faiz <mfcc64 at gmail.com> wrote:

> On 12/16/16, Andreas Cadhalpun <andreas.cadhalpun at googlemail.com> wrote:
> > Suggested-by: Rodger Combs <rodger.combs at gmail.com>
> > Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun at googlemail.com>
> > ---
> >  libavutil/common.h | 2 ++
> >  1 file changed, 2 insertions(+)
> >
> > diff --git a/libavutil/common.h b/libavutil/common.h
> > index 8142b31..00b7504 100644
> > --- a/libavutil/common.h
> > +++ b/libavutil/common.h
> > @@ -99,6 +99,8 @@
> >  #define FFSWAP(type,a,b) do{type SWAP_tmp= b; b= a; a= SWAP_tmp;}while(0)
> >  #define FF_ARRAY_ELEMS(a) (sizeof(a) / sizeof((a)[0]))
> >
> > +#define FF_BAIL_ON_OVERFLOW(ctx, x) if (x) {av_log(ctx, AV_LOG_ERROR,
> > "Overflow check failed: " #x"\n"); return AVERROR_INVALIDDATA;}  
> 
> Where is the overflow check calculation?
> What about functions that need clean up with goto before return?

The whole thing is in "x". Having overflow-safe primitives for each
operation would probably be nicer.