[[!meta copyright="Copyright © 2010 Free Software Foundation, Inc."]]

[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
id="license" text="Permission is granted to copy, distribute and/or modify this
document under the terms of the GNU Free Documentation License, Version 1.2 or
any later version published by the Free Software Foundation; with no Invariant
Sections, no Front-Cover Texts, and no Back-Cover Texts.  A copy of the license
is included in the section entitled [[GNU Free Documentation
License|/fdl]]."]]"""]]

# Emilio Pozuelo Monfort

Email: pochu27@gmail.com

---

# GSoC 2010: Hurd: Fix Compatibility Problems Exposed by Testsuites

Mentor: Carl Fredrik Hammar

## Abstract

This project will consist of identifiying some projects' test suite
failures when executed on GNU/Hurd, debugging them, and if they are
truly GNU/Hurd issues (and not problems in the projects themselves),
fixing them.

## Timeline
* July 18th: GLib finished.
* July 22nd: coreutils finished.
* July 25th: All Perl failures investigated.
* August 5th: Perl finished.
* August 8th: All Python failures investigated.
* August 16th: Python finished.
* August 16th: Firm 'pencils down' date

## TODO
* Finish SCM_RIGHTS patch.
* Send a summary to bug-hurd explaining the O_NOFOLLOW & O_NOTRANS problem.
* Investigate why coreutils' nice test fails.

## Documentation
* [Towards a New Strategy of OS Design, an architectural overview by Thomas Bushnell, BSG](http://www.gnu.org/software/hurd/hurd-paper.html)
* [The Hurd, a presentation by Marcus Brinkmann](http://www.gnu.org/software/hurd/hurd-talk.html)
* [The Hurd Hacking Guide](http://www.gnu.org/software/hurd/hacking-guide/hhg.html)
* [MIG - The MACH Interface Generator](http://www.cs.cmu.edu/afs/cs/project/mach/public/doc/unpublished/mig.ps)

## Log

### July 19th - July 25th
* Initial SCM_RIGHTS implementation. Seems to work when sending pipes, but
  fails miserably when sending fds from an open syscall. No idea why yet.
* Had to build glibc thrice because the system crashed and the fs was totally
  corrupted. I'll build stuff in a separate partition as suggested from now on.

### July 14th - July 18th
* Catched up with email.
* Prepared a patch to implement getsockopt(fd, SOL_SOCKET, SO_TYPE, ...).
  Patch committed to Hurd.
* Addressed comments in the /dev/fd/N patches and resent them.
* Investigated another glib's unix-fd failure: passing fds over a socket using
  sendmsg() doesn't dup them. Created a minimal testcase. Prepared a preliminary
  patch, needs testing and fixing.

### May 26 - July 13th
* Copyright assignment on file.
* Studied a lot to finish my BSc.
* Got the linkat patch (Savannah #29655) committed upstream.

### May 19 - May 26
* Read [MIG - The MACH Interface Generator](http://www.cs.cmu.edu/afs/cs/project/mach/public/doc/unpublished/mig.ps)
* Worked on bug 28934. Send [patches](http://lists.gnu.org/archive/html/bug-hurd/2010-05/msg00108.html) for review.
* Requested GNU libc copyright papers to the FSF again since they didn't arrive the first time.

### May 12 - May 19
* Read http://www.gnu.org/software/hurd/hurd-talk.html
* Half read http://www.gnu.org/software/hurd/hacking-guide/hhg.html
* Read many Hurd interfaces (fs.defs, auth.defs, fsys.defs, io.defs,
  password.defs).

### May 5 - May 12
* Read http://www.gnu.org/software/hurd/hurd-paper.html
* Improved the linkat() patch
* Fixed the issues mentioned in bug 28934, but after doing so I realized
  that wouldn't work well. The only good solution is to pass file_name
  from execve() to the exec server, so we need new RPCs.

### April 28 - May 5
* Submitted a talk proposal on Hurd with Michael Banck for DebConf
* Sent request to assign copyright to the FSF for Hurd/Mach/libc

### Before April 28
* Investigated the glib's gtester problem and tracked it down:
  [bug 28934](https://savannah.gnu.org/bugs/?28934). Prepared a patch
  but it's not good.
* [glib's garray test timeouts on Hurd](https://bugzilla.gnome.org/show_bug.cgi?id=568760).
  The tests passes if the timeout is increased. The current upstream timeout
  (10s) is quite small (it fails on many Debian builds for some Linux arches).
  However on Hurd it needs a very big time it seems (like more than 100s).
  Maybe do an allocation benchmarch?
* Investigated glib's unix-fd test failure: getsockopt() isn't implemented
  on Hurd. Need to implement it in hurd/pflocal/socket.c.
* Investigated coreutils' ln EIEIO, with Samuel's help. linkat() is buggy.
  Reported as [bug 29655](https://savannah.gnu.org/bugs/?29655). Prepared a
  patch for it.
* Investigated coreutils' cp EACCES. Test case: 'mkfifo a && cp -R --copy-contents a b'.
  Problem is that O_NOFOLLOW adds O_NOTRANS.

## Midterm Evaluation
### Accomplished
* Assigned copyright to the FSF.
* Read many documentation and source code.
* /dev/fd/N bug fixed
* Prepared a patch for getsockopt()
* Fixed linkat() problems.
* Investigated bug with O_NOFOLLOW & O_NOTRANS (needs more work).
* Investigated a glib test failure (garray). Not a Hurd issue.
### Downtime
* Studied a lot to finish my BSc. Didn't work on Hurd for a month because of
  that, so that's why I couldn't make a lot of progress (this was known in
  advance, although in the end the downtime was a bit larger than expected).
* There's no expected downtime from now on.