Buildbot

Buildbot Project Service
URL(s)	http://buildbot.scummvm.org
Purpose	Provides automated build services for an increasing number of our supported platforms.
Maintainer(s)	Andre Heider (Dhewg) John Willis (DJWillis)

Introduction

From the buildbot homepage:

The BuildBot is a system to automate the compile/test cycle required by most software projects to validate code changes. By automatically rebuilding and testing the tree each time something has changed, build problems are pinpointed quickly, before other developers are inconvenienced by the failure. The guilty developer can be identified and harassed without human intervention. By running the builds on a variety of platforms, developers who do not have the facilities to test their changes everywhere before checkin will at least know shortly afterwards whether they have broken the build or not. Warning counts, lint checks, image size, compile time, and other build parameters can be tracked over time, are more visible, and are therefore easier to improve.

The overall goal is to reduce tree breakage and provide a platform to run tests or code-quality checks that are too annoying or pedantic for any human to waste their time with. Developers get immediate (and potentially public) feedback about their changes, encouraging them to be more careful about testing before checkin.

You can find the ScummVM buildbot page here.

Goals

• Compile all ports when a commit is done (both trunk and the active branch) to check if it broke one or more ports.
• Notify developers about breakage (and if a following commit fixes it again).
• Provide useful statistics.
• Provide nightly builds of all ports.

Status

What we have so far:

• The bot already polls the Git Server for changes on trunk and the current branch.
• When a change occurs, all ports are being built incrementally.
• Once every 24h (currently 4am CET), a full and clean rebuild is compiled for all ports.
• Provide the nightly builds via HTTP.
• Notify developers upon problems through an IRC bot in IRC Channel.

What's missing:

• Add more toolchains for all missing ports - when possible (see below).
• Notify developers upon problems via mail.

Toolchains

A few requirements must be met to add a toolchain to the buildbot server:

• It must be possible to cross-compile the port from Linux (that might change in the future).
• No custom Makefiles from the backend/ folder, the port has to use the ./configure script.
• The compile process must neither modify nor add anything in the source tree. All builds are performed in external build directories, by invoking the ./configure script in these external directories.
• The port must be fully buildable from scratch with only ./configure arguments and environment variables for it.

The toolchain should be primarily maintained by the port maintainer, but since this requires a little Linux experience, its not a must ;). We will provide assistance with this where possible.

If your toolchain/port is ready to be added, ask sev, joostp or dhewg for an account.

Administration

When the buildbot config files are changed, a user with shell access and sudo privileges needs to run the following commands. It's good practice to do this once buildbot is idle:

sudo -s
/etc/init.d/buildslave stop
/etc/init.d/buildbot stop
cd ~buildbot/buildbot
svn up
/etc/init.d/buildbot start
/etc/init.d/buildslave start

If problems arise, check if all files in the master (~buildbot/master) and slave (~buildbot/slave) directories are owned by the correct user (buildbot:nogroup). If the daemons were incorrectly started, new files might have been created under another user account. In that case:

• stop the daemons (see above)
• fix the permissions with

chown -R buildbot:nogroup ~buildbot/master/*
chown -R buildbot:nogroup ~buildbot/slave/*

• start the daemons