Enhancement request: exclude paths from mkfs.erofs

[Gao Xiang]

Hi David,

On Sat, Nov 30, 2019 at 02:42:37PM -0500, David Michael wrote:
> Hi,
> 
> I'd like to request support for excluding paths in mkfs.erofs similar
> to the -ef (exclude file) option for mksquashfs.  An option that takes
> a file containing a list of paths and glob patterns should be
> sufficient.
> 
> For a simple use case:  I want to build an EROFS image from a Gentoo
> install root, but I don't need development files in it.  An exclude
> option would allow generating a smaller image without the unused files
> while keeping them in the writable source path so additional packages
> could be installed on it later.  This would have /usr/include and
> /usr/lib/*.a for some basic entries in its exclude file.
> 
> If this isn't something that anyone else is interested in implementing
> in the near future, I can try it myself and send a patch after I have
> some time to get more familiar with the code.

That is a useful feature, and I was also thinking that "-pf PSEUDO_FILE"
is useful since root is still needed for device files now...

I have to admit that squashfs has many exist users (thus many exist
developers), but I think in the long term EROFS should perform much better
due to our overall project positioning, ondisk format / runtime advantages
and active community due to paid job maintainers on this as well and open
mind to all new useful features.

For me, now I am busying in XZ algorithm (although there are other random
intra-company exams recently killing much of my time). I have to implement
it to prepare wider scenarios. This is the first priority thing of EROFS.

Cc Guifu. I'm not sure currently he has some extra time working on this.
If some chance, we are very happy that more experienced experts could
join us as well to build a real powerful ROFS solution together.

Files can be simply filtered in the function erofs_mkfs_build_tree.
Any improvements (no matter big or small) are greatly welcomed. :-)

Thanks,
Gao Xiang

> 
> Thanks.
> 
> David