don't return uninitialized memory from bdiff.blocks()
bdiff.blocks() returns a dummy match at the end of both files; the
length of that chunk is never set, so it will sometimes contain random
heap garbage. There are apparently workarounds for this elsewhere:
# bdiff sometimes gives huge matches past eof, this check eats them,
200 Script output follows
content-type: text/plain
content-length: 157
content-disposition: filename=sometext.txt
This is just some random text
that will go inside the file and take a few lines.
It is very boring to read, but computers don't
care about things like that.
host - - [date] "GET /?f=f165dc289438;file=sometext.txt;style=raw HTTP/1.1" 200 -