Filter file inclusion [was: protecting files...]

[Matt McCutchen]

Wayne,

While I was investigating the filter bug, I had some questions about
filter file inclusion.

Most importantly, is an include path followed relative to the filter
file that contains it or the top of the transfer?

Is it legal for one dir-merge file to define another dir-merge
filename?  If so, does rsync handle this case correctly, considering
that the filename might have a directory in front of it?

Is it legal for a dir-merge file to include another ordinary filter
file (not dir-merge)?  If so, rsync needs to elide the included
filters immediately, probably by passing on the xflags that indicated
that the filters in the calling dir-merge file needed to be elided
immediately.

If include paths are usually followed relative to the top of the
transfer, perhaps include paths accessed through a dir-merge file
should be followed relative to the directory that caused the dir-merge
file to be loaded.  That way, dir-merge files will work the same no
matter where the root of the transfer is.

I apologize if some of this doesn't make sense.  I just wanted to make
sure that these issues got considered.

Matt