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Name: Flávio Cruz
Email: flaviocruz at gmail dot com
Some [Hurd stuff](http://opensvn.csie.org/leic/hurd/)
And code: [cl-hurd](http://freehg.org/u/flavioc/cl-hurd/)
hg clone [http://freehg.org/u/flavioc/cl-hurd/](http://freehg.org/u/flavioc/cl-hurd/)
## Summer session
Creating an extensible translator library in lisp using the mig generated stubs.
### What's done
- The library for writing translators is mostly written.
- This library is intended to implement virtual filesystems. Examples are: translators were data is located in a local file (like zipfs, tarfs, rarfs, ...), single file translators (that do content filtering, output of a command, etc), network based filesystems (ftpfs, httpfs, ...), proxy filesystems (like hostmux, usermux, etc..)
- It's possible to specialize the basic translator library and implement new translator classes. This is done using CLOS.
- There is a tree-translator class that makes the managing of a node tree very easy, doing all the work for us, through a simple directory API and implementing the directory callbacks for us.
- There is a simple example (something like zipfs) translator that can expose the directories and file contents of a ZIP file.
- More translator examples include:
- /dev/null translator.
- /dev/zero translator.
- translator that creates a symlink node.
- tmpfs like translator.
- a translator that does proxying between clients and the underlying translator returning all data in upper-case.
- a translator that watches for changes in a file describing the file system structure.
- an IRC translator.
- a categorizer translator: creates a virtual directory containing files listed in a file, each file is categorized with a script. For example, a script can output the music author (in an mp3 file) and then all files will be categorized by author.
- Translator options (manipulated through fsysopts) have a simple and easy to use API.
- All the Mach port manipulation API is available.
- It's possible to send and receive messages. Simple example:
(let* ((spec-mixed (make-message-spec :fields '(:string :integer :char :string :integer :real)))
(msg-mixed (make-message :spec spec-mixed))
(port (port-allocate :right-receive)))
(send-message msg-mixed :remote port :data (list "abc" 42 #\b "cba" 314 3.14))
(receive-message msg-mixed :source port) ; This returns T on success.
(get-message msg-mixed))) ; Returns '("abc" 42 #\b "cba" 314 3.14)
- New message types (like :string, :integer) can be implemented, providing a powerful extension mechanism.
- Creation of symlinks and symlink path resolution.
- Creation of character/block devices, fifos and sockets.
- Patch that opens stdin + stdout to /dev/null.
- Project has been separated into 5 ASDF installable systems:
- Test cases are now written.
### What needs to be done
- Fix fsys-getroot (block happens in trivfs based translators, when they do RPC's to me when I call fsys_getroot to them) and fetch-root (for passive translators).
- Make the library multithreaded (blocked by the pthread conversion project and the unavailable thread support in CLISP)
- Use the socket stubs?
- More documentation
### Project dependencies
- [CFFI](http://common-lisp.net/project/cffi/) (apt-get installable)
- [Flexi streams](http://www.weitz.de/flexi-streams/) (apt-get installable)
- [Trivial garbage](http://www.cliki.net/trivial-garbage) (not in debian repositories)
- [cl-zip](http://common-lisp.net/project/zip/) (only needed for the zip translator)
- [cl-irc](http://common-lisp.net/project/cl-irc/) (for the irc translator)
## To do
- Manually Bootstrapping a Translator
- Translate the Hurd website to Portuguese?
## Completed tasks
- libsvg patch accepted.
- Adapted glibc patch (http://www.schwinge.homeip.net/~thomas/tmp/glibc-patches/0009-2007-07-22-version-of-init-first.c_vs._GCC_4.1.patch.patch)
- Patch to remove some GNUMach IPC warnings and minor cleanup:
- Website patches that correct some encountered typos:
### Documentation read
- GNU/Hurd User's Guide, an introduction to the important concepts and software of the GNU system, written for new users, AKA "GNUbies."
- Towards a New Strategy of OS Design, an architectural overview by Thomas Bushnell, BSG.
- The Hurd, a presentation by Marcus Brinkmann.
- The Hurd Hacking Guide.
- The GNU Mach Reference Manual
- The GNU Hurd Reference Manual
- The Unofficial GNU Mach IPC beginner's guide
- Mach IPC without MIG
- CFFI User's Manual
### Before selection
- Uptime program in C and Lisp using CFFI.
- Hello translator.
### Lisp implementations that run on Hurd