This fixes a bunch of possible overread in avformat with the idiom p +=
strcspn(p, "\n") + 1 (strcspn() can focus on the trailing '\0' if no
'\n' is found, so the +1 leads to an overread).
Note on lavf/matroskaenc: no extra subtitles.o Makefile dependency is
added because only the header is required for ff_subtitles_next_line().
Note on lavf/mpsubdec: code gets slightly complex to avoid an infinite
loop in the probing since there is no more forced increment.
NOTE:
Code of function ff_subtitles_next_line fixed by Alexander Strasser.
The original code from master did test the wrong character, but was
corrected by a subsequent commit. That commit however is not backported,
so it had to be fixed in this commit for the backport.
Conflicts:
libavformat/mpl2dec.c
(cherry picked from commit 90fc00a623de44e137fe1601b91356e8cd8bdd54)
Signed-off-by: Alexander Strasser <eclipse7@gmx.net>
Current MicroDVD AVPackets contain timing information and trailing line
breaks. The data is now only composed of the markup data. Doing this
consistently between text subtitles decoders allows to use different
codec for various formats. For instance, MicroDVD markup is sometimes
found in some VPlayer files. Also, generally speaking, the subtitles
text decoders have no use of these timings (and they must not use them
since it would break any user timing adjustment).
Technically, this is a major ABI break. In practice, a mismatching
lavf/lavc will now error out for MicroDVD decoding. Supporting both
formats requires unnecessary complex and fragile code.
FATE needs update because line breaks in the ASS file were "\n" (because
that's what is used in the original file). ASS format expect "\r\n" line
breaks; this commit fixes this issue. Also note that this "\r\n"
trailing need to be moved at some point from the decoders to the ASS
muxer.
