FuseFS, and ruby threading issues

[Greg Millam]

This one's mostly for folks who know how ruby deals with threads inside
and out.

I have a little project, FuseFS, to provide a userland filesystem
entirely defined in Ruby. (Note: This is *not* rfuse, and is not a
direct implementation of the FUSE api. It is my intention to provide a somewhat
rubyish interface. That is: FuseFS is to FUSE as WEBrick is to the HTTP
protocol + TCPSocket.)

The use of FUSE has given me a few limitations:

* fuse_main literally takes over the program. So "FuseFS.run" basically
hands control of the app over to fuse. It does correctly call Ruby
methods. However, Threads() will not work, and this will likely
interfere with anybody who wants to write, say, a GMailFS clone or
anything using sockets.

* Without pthread support, FuseFS will be unable to deal with concurrent
calls. This also means it can't have anything that reads other files
in itself, and will hang indefinitely until kill -9'd.

What are my options, here? Can I have Ruby stand in its "own" thread,
and when a fuse thread gets an event, have it feed to the ruby thread,
then feed back? (Kinda polling-ish) ? etc?

Any ideas and opinions appreciated.

Thanks,

- Greg Millam

 

[Greg Millam]

Well, I've figured out how to keep ruby in control, so threads, sockets,
etc work just fine.

I've found that I can't make it allow recursive calls, so I'm just
leaving that up to the programmer and user.

Meantime: I have a working initial FuseFS, a little project that I'd
like some usability input on.

http://walker.deafcode.com/code/fusefs.tar.gz

NOTE: It is NOT an implementation of the fuse API - it is a small
implementation that is intended to make making FUSE filesystems easy.

It includes a database->filesystem mapping (sqlfs.rb), and a demo
filesystem that just includes simple tests like a 'colors' file that
prints a diffrent color every time it's 'cat'ted.

Note that this version only has read-only support. I am working on write
support, but am still thinking on how I want to do this.

Have fun and please let me know of any bugs or any ideas you may have.

- Greg Millam