On Sun, Oct 11, 2015 at 2:33 PM, Ronald S. Bultje <rsbul...@gmail.com> wrote: > Hi, > > On Sun, Oct 11, 2015 at 2:15 PM, Ganesh Ajjanagadde <gajja...@mit.edu> > wrote: > >> On Fri, Sep 18, 2015 at 5:02 PM, Michael Niedermayer <michae...@gmx.at> >> wrote: >> > On Fri, Sep 18, 2015 at 09:50:29PM +0200, Nicolas George wrote: >> >> Le jour du Génie, an CCXXIII, Ganesh Ajjanagadde a écrit : >> >> > This patch silences a -Wdiscarded-qualifiers observed with GCC 5.2. >> >> > >> >> > Signed-off-by: Ganesh Ajjanagadde <gajjanaga...@gmail.com> >> >> > --- >> >> > libavformat/rtmpcrypt.c | 2 +- >> >> > 1 file changed, 1 insertion(+), 1 deletion(-) >> >> >> >> I am not sure this is correct: the buffer is const for a reason, the >> warning >> >> is right. An application would be completely allowed to give a buffer in >> >> read-only memory, or to reuse the contents of the buffer afterwards. >> >> >> >> Actually, I suspect this muxer, if used as first output in the tee >> muxer, >> >> would cause the next outputs to be corrupt. >> > >> > IIRC the code is safe, just ugly >> > the writing only occurs if handshaked is set, which is only set >> > by ff_rtmpe_update_keystream() which is not part of the public >> > interface and only called from libavformat/rtmpproto.c >> > i assume but did not double check that libavformat/rtmpproto.c >> > calls the functions so that writable buffers are used >> > >> > >> >> >> >> The correct fix would probably be to allocate a new buffer, probably >> keeping >> >> it in the context for performances reasons instead of allocating each >> time. >> > >> > id need to double check but i think the calling code possibly uses >> > the written buffer with the expectation that it has been updated >> > >> > if that is so then such fix would break it. >> >> Have you checked the code and confirmed that this patch is fine? > > > I don't think the explanation makes the patch fine, the explanation just > says that there's no actual issue being hidden behind the warning. It > sounds like this code needs some refactoring...
Unfortunately, I can't see a clean solution to this without changing some API. > > Ronald > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel