[FFmpeg-devel] Broken compile with latest libavutil/common.h

[Michael Niedermayer]

On Thu, Jan 15, 2009 at 02:37:56PM +0000, M?ns Rullg?rd wrote:
> Michael Niedermayer <michaelni at gmx.at> writes:
> 
> > On Thu, Jan 15, 2009 at 12:43:27AM +0000, M?ns Rullg?rd wrote:
> >> Aurelien Jacobs <aurel at gnuage.org> writes:
> >> > +/**
> >> > + * converts fourcc string to int
> >> > + */
> >> > +static inline av_pure int ff_get_fourcc(const char *s){
> >> > +    assert( strlen(s)==4 );
> >> > +    return (s[0]) + (s[1]<<8) + (s[2]<<16) + (s[3]<<24);
> >> > +}
> >> 
> >> This looks a lot like AV_RL32().  
> >
> > indeed and i wouldnt mind seeing all ff_get_fourcc replaced by it
> >
> >> BTW, assert(strlen(s) ... ) is a
> >> stupid idea.  If there's bad data, what's to say there will be a null
> >> terminator anywhere close?
> >
> > nothing, but if its not it will either segfault by reading to much
> > or the assert will end the program thus i dont see it as a problem.
> 
> What if it doesn't hit unreadable memory, but hits a memory-mapped
> device where reads have side-effects?

good point even if i wouldnt consider this a very realistic scenario
but as the code can and should be replaced by direct use of AV_RL32() theres
little point in fixing this ...

[...]

-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

There will always be a question for which you do not know the correct awnser.
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