Dextrose/Building

Build system

We use olpc-os-builder, a tool used by OLPC to create official and customized system images. Our version contains local customizations specific to Dextrose and some patches that should be upstreamed.

Build host requirements

The olpc-os-builder machinery has been used successfully with systems running Fedora 11 i386 through Fedora 13 x86_64.

What the host system runs shouldn't matter much, because all the work is being done in a chroot environment, but olpc-os-builder is known to fail on Ubuntu due to a missing dependency.

How to create a build

Checkout our local tree:

 git clone git://git.sugarlabs.org/dextrose/mainline.git

One time preparation

 yum upgrade
 yum install libtomcrypt-devel bitfrost make gcc mtd-utils
 make

Build:

 time sudo ./osbuilder.py examples/f11-xo1-py.ini

Wait 15 minutes

Serve hot

Signing

Put the 4 signing keys somewhere in your home:

bernie@robbie:~$ ll src/olpc/keys/
-rw-------. 1 bernie bernie 1,2K Feb  5  2009 pyo1.private
-rw-------. 1 bernie bernie  270 Feb  5  2009 pyo1.public
-rw-------. 1 bernie bernie 1,2K Feb  5  2009 pys1.private
-rw-------. 1 bernie bernie  270 Feb  5  2009 pys1.public
-rw-------. 1 bernie bernie 1,2K Feb  5  2009 pyw1.private
-rw-------. 1 bernie bernie  270 Feb  5  2009 pyw1.public

Make sure the keys are NOT world-readable

Edit the paths in the [signing] section of examples/f11-xo1-py.ini

Publishing the images

I'm currently publishing selected builds in my public html folder.

Signed builds should be published only if they implement the OLPC anti-theft system (OATS). Signing does not have anything to do with quality or endorsement (i.e. signed builds are not necessarily bug-free).

TODO: We don't have a place for publishing official images yet

TODO: We don't have a procedure for releasing builds to field technicians (we may use repo.paraguayeduca.org in the future)

TODO: We don't keep release notes for our builds (we should probably use the wiki)

Customizing the build

The topic of is too vast to discuss in detail here. Start by reading http://git.paraguayeduca.org/gitweb/users/bernie/olpc-os-builder.git/blob_plain/HEAD:/doc/README README] in the olpc-os-builder tree. Then, as needed, read the various README files contained in the modules directory.

Being a Build Master involves knowledge of many workflows, including:

Building Sugar in sugar-jhbuild.

Dealing with yum and rpm.

Understanding the Fedora packaging workflow and conventions.

Creating yum package repositories with [1].

Uploading activities to [2].

General understanding of the Linux system plumbing infrastructure: kernel,

udev, dbus, DeviceKit, NetworkManager, Xorg...

Flashing laptops and debugging any problems

Interaction with the Sugar and OLPC community to solve issues and minimize our divergence from the official builds.

Upstream

Our upstream code comes from dev.laptop.org:

git remote add olpc git://dev.laptop.org/projects/olpc-os-builder
git fetch olpc
git log olpc/master

Building custom kernels

$ git clone git://git.paraguayeduca.org/users/bernie/olpc-2.6
$ cd olpc-2.6
$ setarch i386 make ARCH=i386 xo_1-kernel-rpm