Batched fixes from libpng16: PNG_IMAGE_PNG_SIZE_MAX macro fix, contrib/libtests
exit(77) change to just do that for configure and changes to pngstest to
(by default) make random backgrounds on a per-file, not per-session, basis.
Signed-off-by: John Bowler <jbowler@acm.org>
Fixes the case where IDAT is treated as unknown and saved; the first IDAT chunk
ends up 'before' IDAT, the rest 'after', pngunknown has to take this into
account since it checks before and after.
Most of these are back-portable to earlier versions (contrib/libtests
should just work with earlier versions), however the 1.7 specific
changes in pngvalid mean that it probably won't work against 1.7 without
the commits following this one.
Signed-off-by: John Bowler <jbowler@acm.org>
the useful side effect of avoiding a bogus warning generated by the latest
version of the Intel C compiler (it objects to
condition ? string-literal : string-literal).
