pbuilder 利用マニュアル

利用と操作方法について

Uekawa Junichi [FAMILY Given]

This documentation is a work in progress; it might be incomplete and outdated.


目次

1. pbuilder の紹介
1. pbuilder の目的
2. pbuilder を利用する
1. base chroot イメージの tar 玉の作成
2. base.tgz の更新
3. base.tgz を利用してパッケージをビルドする
4. Facilitating Debian Developers' typing: pdebuild
5. 設定ファイル
6. chroot 内部で root 以外でパッケージをビルドする
7. pbuilder をバックポートに活用する
8. パッケージを大量にビルドする
9. 自動バックポートスクリプト
10. pbuilder を自動テストに利用する
11. pbuilder でその他のコンパイラでのビルドを試験する
3. user-mode-linux を pbuilder で利用する
1. user-mode-linux の設定
2. rootstrap の設定
3. pbuilder-uml の設定
4. pbuilder-user-mode-linuxを実行する場合の検討項目
5. pbuilder-user-mode-linux を複数同時に実行させる
6. Using pbuilder-user-mode-linux as a wrapper script to start up a virtual machine
4. FAQ (よくある質問)
1. pbuilder create が失敗する
2. bind mount できないディレクトリ
3. ビルド失敗の調査のために pbuilder 環境にログインする
4. 環境を変更するために pbuilder 環境にログインする
5. BUILDRESULTUID を sudo のセッションに追加する
6. $TMPDIRの使い方について
7. Creating a shortcut for running pbuilder with a specific distribution
8. Using environmental variables for running pbuilder for a specific distribution
9. Using special apt sources lists, and local packages
10. How to get pbuilder to run apt-get update before trying to satisfy build-dependencies
11. pbuilder login で bash のプロンプトを変更する
12. Creating a chroot reminder
13. Using /var/cache/apt/archives for the package cache
14. pbuilder back ported to stable Debian releases
15. Warning about LOGNAME not being defined
16. Cannot Build-conflict against an essential package
17. Avoiding the "ln: Invalid cross-device link" message
18. Using fakechroot
19. Using debconf inside pbuilder sessions
20. nodev mount options hinder pbuilder activity
21. pbuilder が遅い
22. Using pdebuild to sponsor package
23. Why is there a source.changes file in ../?
24. amd64 and i386-mode
25. Using tmpfs for buildplace
26. svn-buildpackage を pbuilder で利用する
5. Troubleshooting and development
1. Reporting bugs
2. Mailing list
3. IRC Channel
4. Information for pbuilder developers
6. Other uses of pbuilder
1. pbuilder を小規模な実験のために活用する
2. Running little programs inside the chroot
7. Experimental or wishlist features of pbuilder
1. LVMの活用
2. cowdancer の活用
3. tar.gz を利用しないで pbuilder を利用する
4. pbuilder を vserver で利用する
5. Usage of ccache
8. 参考文献
1. chroot 外部のディレクトリ構造
2. chroot 内部のディレクトリ構造
9. 些細な過去の経緯の詳細
1. マニュアルの履歴
2. Possibly inaccurate Background History of pbuilder
2.1. The Time Before pbuilder
2.2. pbuilder の誕生
2.3. そして二年目の人生
2.4. pbuilder の5年目

表の一覧

5.1. テストスイートのディレクトリ構造
8.1. chroot 内部のディレクトリ構造
8.2. chroot 内部のディレクトリ構造

第1章 pbuilder の紹介

1. pbuilder の目的

pbuilder stands for Personal Builder, and it is an automatic Debian Package Building system for personal development workstation environments. pbuilder aims to be an easy-to-set-up system for auto-building Debian packages inside a clean-room environment, so that it is possible to verify that a package can be built on most Debian installations. The clean-room environment is achieved through the use of a base chroot image, so that only minimal packages will be installed inside the chroot.

Debian ディストリビューションはソースコードつきのフリーソフトウェアにより構成されています。Debianの「main」セクションにあるソフトウェアは、Build-depend (ビルド時依存関係)として指定されたDebianの「main」セクションにあるパッケージのみがインストールされている状態でビルドできなければなりません。

主なる pbuilder の目的は、他の自動ビルドシステムとは違います。それは、パッケージをできるだけビルドできるようなことを目的としていないところです。パッケージが何を必要としているのかを想像しようとはしません。また選択が可能であれば、最悪な選択をする場合もあります。

この方針を採用することで、 pbuilder は、 pbuilder で試験したパッケージはほとんどのDebianがインストールされた環境でビルドできるように確認することができます。これによってDebian全体としてのソースコードのビルドしやすさの向上を目指しています。

The goal of making Debian buildable from source is somewhat accomplished, and has seen good progress. In the past age of Debian 3.0, there were many problems when building from source. More recent versions of Debian are much better.

第2章 pbuilder を利用する

操作には、いくつかの簡単なコマンドがあります。pbuilder createpbuilder update、そして pbuilder build コマンドがよく使われます。ひとつづつ見ていきましょう。

1. base chroot イメージの tar 玉の作成

pbuilder create will create a base chroot image tar-ball (base.tgz). All other commands will operate on the resulting base.tgz. If the Debian release to be created within chroot is not going to be "sid" (which is the default), the distribution code-name needs to be specified with the --distribution command-line option.

debootstrap [1] is used to create the bare minimum Debian installation, and then build-essential packages are installed on top of the minimum installation using the apt-get inside the chroot.

For more thorough documentation of command-line options, see the pbuilder(8) manual page. Some configuration will be required for /etc/pbuilderrc for the mirror site [2] to use, and proxy configuration may be required to allow access through HTTP. See the pbuilderrc(5) manual page for details.

2. base.tgz の更新

pbuilder update will update the base.tgz. It will extract the chroot, invoke apt-get update and apt-get dist-upgrade inside the chroot, and then recreate the base.tgz (the base tar-ball).

It is possible to switch the distribution for which the base.tgz is targeted at at this point. Specify --distribution sid --override-config to change the distribution to sid. [3]

For more thorough documentation of command-line options, see the pbuilder(8) manual page.

3. base.tgz を利用してパッケージをビルドする

To build a package inside the chroot, invoke pbuilder build whatever.dsc. pbuilder will extract the base.tgz to a temporary working directory, enter the directory with chroot, satisfy the build-dependencies inside chroot, and build the package. The built packages will be moved to a directory specified with the --buildresult command-line option.

The --basetgz option can be used to specify which base.tgz to use.

pbuilder will extract a fresh base chroot image from base.tgz. (base.tgz is created with the pbuilder create, and updated with the pbuilder update). The chroot is populated with build-dependencies by parsing debian/control and invoking apt-get.

For more thorough documentation of command-line options, see the pbuilder(8) manual page

4. Facilitating Debian Developers' typing: pdebuild

pdebuild is a little wrapper script that does the most frequent of all tasks. A Debian Developer may try to run debuild, and build a package inside a Debian source directory. pdebuild will allow similar control, and allow the package to be built inside the chroot, to check that the current source tree will build happily inside the chroot.

pdebuild calls dpkg-source to build the source packages, and then invokes pbuilder on the resulting source package. However, unlike debuild, the resulting deb files will be found in the --buildresult directory.

See the pdebuild(1) manual page for more details.

There is a slightly different mode of operation available in pdebuild since version 0.97. pdebuild usually runs debian/rules clean outside of the chroot; however, it is possible to change the behavior to run it inside the chroot with the --use-pdebuild-internal. It will try to bind mount the working directory inside chroot, and run dpkg-buildpackage inside. It has the following characteristics, and is not yet the default mode of operation.

  • Satisfies build-dependency inside the chroot before creating source package (which is a good point that default pdebuild could not do).

  • 作業ディレクトリに chroot 内部から変更を加えられます。

  • pdebuild でビルドできることは pbuilder で必ず動くということが保証されるわけではないです。

  • ソースパッケージを作るステップ自体が失敗した場合に、その chroot を利用するセッションは無駄に終わります(chroot の作成には時間がかかる、cowdancer 等で改善します。)

  • Does not work in the same manner as it used to; for example, --buildresult does not have any effect.

  • The build inside chroot is run with the current user outside chroot.

5. 設定ファイル

設定をすべてコマンドラインで指定することも可能です。しかし、入力を簡便にするために、設定ファイルを利用することもできます。

/etc/pbuilderrc and ${HOME}/.pbuilderrc are read in when pbuilder is invoked. The possible options are documented in the pbuilderrc(5) manual page.

It is useful to use the --configfile option to load up a preset configuration file when switching between configuration files for different distributions.

Please note that ${HOME}/.pbuilderrc supersedes system settings. A caveat is that if you have some configuration, you may need to tweak the configuration to work with new versions of pbuilder when upgrading.

6. chroot 内部で root 以外でパッケージをビルドする

pbuilder requires full root privilege when it is satisfying the build-dependencies, but most packages do not need root privilege to build, or even refuse to build when they are built as root. pbuilder can create a user which is only used inside pbuilder and use that user id when building, and use the fakeroot command when root privilege is required.

The BUILDUSERID configuration option should be set to a value for a user id that does not already exist on the system, so that it is more difficult for packages that are being built with pbuilder to affect the environment outside the chroot. When the BUILDUSERNAME configuration option is also set, pbuilder will use the specified user name and fakeroot for building packages, instead of running as root inside chroot.

fakeroot の方法を利用している場合でも、pbuilder は root 権限が必要な場面では root 権限で稼働します。例えば、chroot内部にパッケージをインストールする時にはpbuilder は root 権限で稼働します。

pbuilder を root 権限を必要としないで利用する方法については、 user-mode-linux の利用が必要です。 3章user-mode-linux を pbuilder で利用する で説明しています。

7. pbuilder をバックポートに活用する

pbuilder は古いディストリビューションのchroot を作成し、そこでパッケージをビルドすることで、Debian の最新版のディストリビューションからソフトウエアをバックポートするのに利用することが可能です。いくつかの点を検討する必要があり、次の理由により全自動でバックポートすることは現実的では無く、手動での作業も必要になるでしょう:

  • unstableのパッケージが unstable にしかないパッケージや、unstable にしかないバージョンのパッケージに依存している場合がある。つまり、stable では Build-Depends: を充足することができない(さらなるバックポートが必要になる)。

  • stable ディストリビューションには unstable で修正しているバグが含まれており、ワークアラウンドが必要になる。

  • unstable のパッケージが unstable 上であってもビルドしない場合がある。

8. パッケージを大量にビルドする

pbuilder は操作がインタラクティブではないため、自動的に動かすことができる。pbuilder を複数のパッケージに関して、インタラクティブじゃないように実行することができます。それをするためのスクリプトはいくつか存在します。上川は2001年からそのようなスクリプトを実行し、 pbuilder でビルドできない場合についてバグ報告をしていました。次のような問題が発見されました:

  • 依存関係を充足させるためのインストールは非インタラクティブに行われる必要がありますが、一部のパッケージはインタラクティブな操作がないとインストールできないくらいに壊れているものがあります(postgresqlなど).

  • When a library package breaks, or gcc/gcj/g++ breaks, or even bison, a large number of build failures are reported. (gcj-3.0 had no "javac", bison got more strict, etc.)

  • 一部の人はビルド失敗の報告に敵対的なので注意しましょう。

2002年ころのpbuilder の実行により初期のバグは洗いだされました。しかし、このように移行に関連したDebian全体に影響するような問題はときどき発生します。回帰テストには価値があるのです。

上川が利用したスクリプトは今 pbuilder ディストリビューションに含まれています。/usr/share/doc/pbuilder/examples/pbuildd/ にあり、設定は、 /etc/pbuilder/pbuildd-config.sh が設定ファイルです。pbuilder になれている人であれば簡単に設定することができるはずです。しばらく実行されていたため、自分のシステムでも実行できるでしょう。ただ、まだ新しいので問題があれば Debian BTS に登録してください。

pbuildd の設定について気にしておくところがいくつかあります。

  • ビルドしないパッケージの一覧ファイル ./avoidlist が存在する必要があります。

  • It will try building anything, even packages that are not intended for your architecture.

  • 任意のビルドスクリプトを実行しているため、 root 権限で実行しないために、 pbuilder のfakeroot オプションを利用するのがよいでしょう。

  • すべてのビルドが有限時間で完了することが保証されているわけではありません、そのためタイムアウトを準備しておくことが必要かもしれません。そうしないとpbuilddは悪いビルドでずっと待ち状態になる可能性もあります。

  • Some packages require a lot of disk space; around 2GB seems to be sufficient for the largest packages for the time being. If you find otherwise, please inform the maintainer of this documentation.

9. 自動バックポートスクリプト

一部の人は pbuilder を一部のパッケージを自動的に stable ディストリビューションにバックポートするために利用しています。

I would like some information on how people are doing it. I would appreciate any feedback or information on how you are doing it, or any examples.

10. pbuilder を自動テストに利用する

pbuilder は、自動的なテストのために利用することができます。フックを配置することができ、そのフックは chroot 内部にパッケージをインストールしたり実行したりその他のいろいろなことを実行することができます。実行可能なテストとアイデアは次です:

  • Automatic install-remove-install-purge-upgrade-remove-upgrade-purge test-suite (distributed as an example, B91dpkg-i), or just check that everything installs somewhat (execute_installtest.sh).

  • 自動的にlintianを実行する (例として /usr/share/doc/pbuilder/examples/B90lintianが配布されている)。

  • Automatic debian-test of the package? The debian-test package has been removed from Debian. A pbuilder implementation can be found as debian/pbuilder-test directory, implemented through the B92test-pkg script.

To use the B92test-pkg script, first, add it to your hook directory. [4]. The test files are shell scripts placed in debian/pbuilder-test/NN_name (where NN is a number) following the run-parts standard[5] for file names. After a successful build, packages are first tested for installation and removal, and then each test is run inside the chroot. The current directory is the top directory of the source-code. This means you can expect to be able to use the ./debian/ directory from inside your scripts.

Example scripts for use with pbuilder-test can be found in /usr/share/doc/pbuilder/examples/pbuilder-test.

11. pbuilder でその他のコンパイラでのビルドを試験する

Most packages are compiled with gcc or g++ and use the default compiler version, which was gcc 2.95 for Debian GNU/Linux 3.0 (i386). However, Debian 3.0 was distributed with other compilers, under package names such as gcc-3.2 for gcc compiler version 3.2. It was therefore possible to try compiling packages against different compiler versions. pentium-builder provides an infrastructure for using a different compiler for building packages than the default gcc, by providing a wrapper script called gcc that calls the real gcc. To use pentium-builder in pbuilder, it is possible to set up the following in the configuration:

EXTRAPACKAGES="pentium-builder gcc-3.2 g++-3.2"
export DEBIAN_BUILDARCH=athlon
export DEBIAN_BUILDGCCVER=3.2

It will instruct pbuilder to install the pentium-builder package and also the GCC 3.2 compiler packages inside the chroot, and set the environment variables required for pentium-builder to function.



[1] debootstrap か cdebootstrap か選択することができます

[2] 公開ミラーに多数のアクセス負荷をかけないため、ミラーはローカルミラーであることが望ましいです。apt-proxy などのツールの活用を推奨します。

[3] アップグレードしかサポートされていません。Debianはダウングレードをサポートしていません(現時点では?)。

[4] It is possible to specify a --hookdir /usr/share/doc/pbuilder/examples command-line option to include all example hooks as well.

[5] run-parts(8) を参照してください。例えば、ファイル名に '.' はふくめられません。

第3章 user-mode-linux を pbuilder で利用する

It is possible to use user-mode-linux by invoking pbuilder-user-mode-linux instead of pbuilder. pbuilder-user-mode-linux doesn't require root privileges, and it uses the copy-on-write (COW) disk access method of User-mode-linux, which typically makes it much faster than the traditional pbuilder.

User-mode-linux is a somewhat less proven platform than the standard Unix tools that pbuilder relies on (chroot, tar, and gzip) but mature enough to support pbuilder-user-mode-linux since its version 0.59. And since then, pbuilder-user-mode-linux has seen a rapid evolution.

The configuration of pbuilder-user-mode-linux goes in three steps:

  • user-mode-linux の設定

  • rootstrap の設定

  • pbuilder-uml の設定

1. user-mode-linux の設定

user-mode-linux isn't completely trivial to set up. It would probably be useful to acquaint yourself with it a bit before attempting to use rootstrap or pbuilder-user-mode-linux. For details, read /usr/share/doc/uml-utilities/README.Debian and the user-mode-linux documentation. (It's in a separate package, user-mode-linux-doc.)

user-mode-linux requires the user to be in the uml-net group in order to configure the network unless you are using slirp.

If you compile your own kernel, you may want to verify that you enable TUN/TAP support, and you might want to consider the SKAS patch.

2. rootstrap の設定

rootstrap is a wrapper around debootstrap. It creates a Debian disk image for use with UML. To configure rootstrap, there are several requirements.

  • rootstrap パッケージをインストールします。

  • TUN/TAP only: add the user to the uml-net group to allow access to the network

    adduser dancer uml-net

  • TUN/TAPを利用している場合: カーネルが TUN/TAP インタフェースをサポートしていることを確認してください。必要であればカーネルをリビルドしてください。

  • Set up /etc/rootstrap/rootstrap.conf. For example, if the current host is 192.168.1.2, changing the following entries to something like this seems to work.

    transport=tuntap
    interface=eth0
    gateway=192.168.1.1
    mirror=http://192.168.1.2:8081/debian
    host=192.168.1.198
    uml=192.168.1.199
    netmask=255.255.255.0

    Some experimentation with configuration and running rootstrap ~/test.uml to actually test it would be handy.

    Using slirp requires less configuration. The default configuration comes with a working example.

3. pbuilder-uml の設定

以下の設定が必要です:

  • pbuilder-uml をインストールする

  • Set up the configuration file /etc/pbuilder/pbuilder-uml.conf in the following manner. It will be different for slirp.

    MY_ETH0=tuntap,,,192.168.1.198
    UML_IP=192.168.1.199
    UML_NETMASK=255.255.255.0
    UML_NETWORK=192.168.1.0
    UML_BROADCAST=255.255.255.255
    UML_GATEWAY=192.168.1.1
    PBUILDER_UML_IMAGE="/home/dancer/uml-image"

    Also, it needs to match the rootstrap configuration.

  • Make sure BUILDPLACE is writable by the user. Change BUILDPLACE in the configuration file to a place where the user has access.

  • Run pbuilder-user-mode-linux create --distribution sid to create the image.

  • Try running pbuilder-user-mode-linux build.

4. pbuilder-user-mode-linuxを実行する場合の検討項目

pbuilder-user-mode-linux emulates most of pbuilder, but there are some differences.

  • pbuilder-user-mode-linux does not support all options of pbuilder properly yet. This is a problem, and will be addressed as specific areas are discovered.

  • /tmp is handled differently inside pbuilder-user-mode-linux. In pbuilder-user-mode-linux, /tmp is mounted as tmpfs inside UML, so accessing files under /tmp from outside user-mode-linux does not work. It affects options like --configfile, and when trying to build packages placed under /tmp.

5. pbuilder-user-mode-linux を複数同時に実行させる

pbuilder-user-mode-linux を同一システム上で同時に複数実行させるにはいくつか注意するべき点があります。

  • The create and update methods must not be run when a build is in progress, or the COW file will be invalidated.

  • If you are not using slirp, user-mode-linux processes that are running in parallel need to have different IP addresses. Just trying to run the pbuilder-user-mode-linux several times will result in failure to access the network. But something like the following will work:

    for IP in 102 103 104 105; do
      xterm -e pbuilder-user-mode-linux build --uml-ip 192.168.0.$IP \
        20030107/whizzytex_1.1.1-1.dsc &
    done

    When using slirp, this problem does not exist.

6. Using pbuilder-user-mode-linux as a wrapper script to start up a virtual machine

It is possible to use pbuilder-user-mode-linux for other uses than just building Debian packages. pbuilder-user-mode-linux login will let a user use a shell inside the user-mode-linux pbuilder base image, and pbuilder-user-mode-linux execute will allow the user to execute a script inside the image.

You can use the script to install ssh and add a new user, so that it is possible to access inside the user-mode-linux through ssh.

Note that it is not possible to use a script from /tmp due to the way pbuilder-user-mode-linux mounts a tmpfs at /tmp.

The following example script may be useful in starting a sshd inside user-mode-linux.

#!/bin/bash

apt-get install -y ssh xbase-clients xterm
echo "enter root password"
passwd
cp /etc/ssh/sshd_config{,-}
sed 's/X11Forwarding.*/X11Forwarding yes/' /etc/ssh/sshd_config- > /etc/ssh/sshd_config

/etc/init.d/ssh restart
ifconfig
echo "Hit enter to finish"
read

第4章 FAQ (よくある質問)

Here, known problems and frequently asked questions are documented. This portion was initially available in README.Debian file, but moved here.

1. pbuilder create が失敗する

It often happens that pbuilder cannot create the latest chroot. Try upgrading pbuilder and debootstrap. It is currently only possible to create software that handles the past. Future prediction is a feature which may be added later after we have become comfortable with the past.

There are people who occasionally back port debootstrap to stable versions; hunt for them.

When there are errors with the debootstrap phase, the debootstrap script needs to be fixed. pbuilder does not provide a way to work around debootstrap.

2. bind mount できないディレクトリ

Because of the way pbuilder works, there are several directories that cannot be bind-mounted when running pbuilder. The directories include /tmp, /var/cache/pbuilder, and system directories such as /etc and /usr. The recommendation is to use directories under the user's home directory for bind-mounts.

3. ビルド失敗の調査のために pbuilder 環境にログインする

It is possible to invoke a shell session after a build failure. Example hook scripts are provided as C10shell and C11screen scripts. The C10shell script will start bash inside chroot, and the C11screen script will start a GNU screen inside the chroot.

4. 環境を変更するために pbuilder 環境にログインする

It is sometimes necessary to modify the chroot environment. login will remove the contents of the chroot after logout. It is possible to invoke a shell using hook scripts. pbuilder update executes 'E' scripts, and a sample for invoking a shell is provided as C10shell.

$ mkdir ~/loginhooks
$ cp C10shell ~/loginhooks/E10shell
$ sudo pbuilder update --hookdir ~/loginhooks/E10shell

It is also possible to add --save-after-exec and/or --save-after-login options to the pbuilder login session to accomplish the goal. It is possible to add the --uml-login-nocow option to pbuilder-user-mode-linux login session as well.

5. BUILDRESULTUID を sudo のセッションに追加する

It is possible to set

BUILDRESULTUID=$SUDO_UID

in pbuilderrc to set the proper BUILDRESULTUID when using sudo.

6. $TMPDIRの使い方について

If you are setting $TMPDIR to an unusual value, of other than /tmp, you will find that some errors may occur inside the chroot, such as dpkg-source failing.

There are two options: you may install a hook to create that directory, or set

export TMPDIR=/tmp

in pbuilderrc. Take your pick.

An example script is provided as examples/D10tmp with pbuilder.

7. Creating a shortcut for running pbuilder with a specific distribution

When working with multiple chroots, it would be nice to work with scripts that reduce the amount of typing. An example script, pbuilder-distribution.sh, is provided as an example. Invoking the script as pbuilder-squeeze will invoke pbuilder with a squeeze chroot.

8. Using environmental variables for running pbuilder for a specific distribution

This section[6] describes briefly a way to set up and use multiple pbuilder setups by creating a pbuilderrc configuration in your home path ($HOME/.pbuilderrc) and using the variable "DIST" when running pbuilder or pdebuild.

First, set up $HOME/.pbuilderrc to look like:

if [ -n "${DIST}" ]; then
        BASETGZ="`dirname $BASETGZ`/$DIST-base.tgz"
        DISTRIBUTION="$DIST"
        BUILDRESULT="/var/cache/pbuilder/$DIST/result/"
        APTCACHE="/var/cache/pbuilder/$DIST/aptcache/"
fi

Then, whenever you wish to use pbuilder for a particular distro, assign a value to "DIST" that is one of the distros available for Debian or any Debian based distro you happen to be running (i.e., whatever is found under /usr/lib/debootstrap/scripts).

Here are some examples for running pbuilder or pdebuild:

DIST=gutsy sudo pbuilder create

DIST=sid sudo pbuilder create --mirror http://http.us.debian.org/debian

DIST=gutsy sudo pbuilder create \
        --othermirror "deb http://archive.ubuntu.com/ubuntu gutsy universe \
        multiverse"

DIST=gutsy sudo pbuilder update

DIST=sid sudo pbuilder update --override-config --mirror \
http://http.us.debian.org/debian \
--othermirror "deb http://http.us.debian.org/debian sid contrib non-free"

DIST=gutsy pdebuild

9. Using special apt sources lists, and local packages

If you have some very specialized requirements on your apt setup inside pbuilder, it is possible to specify them through the --othermirror option. Try something like: --othermirror "deb http://local/mirror stable main|deb-src http://local/source/repository ./"

To use the local file system instead of HTTP, it is necessary to do bind-mounting. --bindmounts is a command-line option useful for such cases.

It might be convenient to use your built packages from inside the chroot. It is possible to automate the task with the following configuration. First, set up pbuilderrc to bindmount your build results directory.

BINDMOUNTS="/var/cache/pbuilder/result"

Then, add the following hook

# cat /var/cache/pbuilder/hooks/D70results
#!/bin/sh
cd /var/cache/pbuilder/result/
/usr/bin/dpkg-scanpackages . /dev/null > /var/cache/pbuilder/result/Packages
/usr/bin/apt-get update

This way, you can use deb file:/var/cache/pbuilder/result

To add a new apt-key inside chroot:

sudo pbuilder --login --save-after-login
# apt-key add - <<EOF
...public key goes here...
EOF
# logout

10. How to get pbuilder to run apt-get update before trying to satisfy build-dependencies

You can use hook scripts for this. D scripts are run before satisfying build-dependency.

This snippet comes from Ondrej Sury.

11. pbuilder login で bash のプロンプトを変更する

To make distinguishing bash prompts inside pbuilder easier, it is possible to set environment variables such as PS1 inside pbuilderrc

With versions of bash more recent than 2.05b-2-15, the value of the debian_chroot variable, if set, is included in the value of PS1 (the Bash prompt) inside the chroot. In prior versions of bash,[7] setting PS1 in pbuilderrc worked.

Example of debian_chroot:

	export debian_chroot="pbuild$$"

Example of PS1:

	export PS1="pbuild chroot 32165 # "

12. Creating a chroot reminder

Bash prompts will help you remember that you are inside a chroot. There are other cases where you may want other signs of being inside a chroot. Check out the examples/F90chrootmemo hook script. It will create a file called /CHROOT inside your chroot.

13. Using /var/cache/apt/archives for the package cache

For the help of low-bandwidth systems, it is possible to use /var/cache/apt/archives as the package cache. Just specify it instead of the default /var/cache/pbuilder/aptcache.

It is however not possible to do so currently with the user-mode-linux version of pbuilder, because /var/cache/apt/archives is usually only writable by root.

Use of dedicated tools such as apt-proxy is recommended, since caching of packages would benefit the system outside the scope of pbuilder.

14. pbuilder back ported to stable Debian releases

Currently, a stable back port of pbuilder is available at backports.org.

15. Warning about LOGNAME not being defined

You might see a lot of warning messages when running pbuilder.

	dpkg-genchanges: warning: no utmp entry available and LOGNAME not defined; using uid of process (1234)

It is currently safe to ignore this warning message. Please report back if you find any problem with having LOGNAME unset. Setting LOGNAME caused a few problems when invoking chroot. For example, dpkg requires getpwnam to succeed inside chroot, which means LOGNAME and the related user information have to be set up inside chroot.

16. Cannot Build-conflict against an essential package

pbuilder does not currently allow Build-Conflicts against essential packages. It should be obvious that essential packages should not be removed from a working Debian system, and a source package should not try to force removal of such packages on people building the package.

17. Avoiding the "ln: Invalid cross-device link" message

By default, pbuilder uses hard links to manage the pbuilder package cache. It is not possible to make hard links across different devices; and thus this error will occur, depending on your set up. If this happens, set

APTCACHEHARDLINK=no

in your pbuilderrc file. Note that packages in APTCACHE will be copied into the chroot local cache, so plan for enough space on the BUILDPLACE device.

18. Using fakechroot

It is possible to use fakechroot instead of being root to run pbuilder; however, several things make this impractical. fakechroot overrides library loads and tries to override default libc functions when providing the functionality of virtual chroot. However, some binaries do not use libc to function, or override the overriding provided by fakechroot. One example is ldd. Inside fakechroot, ldd will check the library dependency outside of the chroot, which is not the expected behavior.

To work around the problem, debootstrap has a --variant fakechroot option. Use that, so that ldd and ldconfig are overridden.

Make sure you have set your LD_PRELOAD path correctly, as described in the fakechroot manpage.

19. Using debconf inside pbuilder sessions

To use debconf inside pbuilder, setting DEBIAN_FRONTEND to readline in pbuilderrc should work. Setting it to dialog should also work, but make sure whiptail or dialog is installed inside the chroot.

20. nodev mount options hinder pbuilder activity

If you see messages such as this when building a chroot, you are mounting the file system with the nodev option.

	/var/lib/dpkg/info/base-files.postinst: /dev/null: Permission denied

You will also have problems if you mount the file system with the noexec option, or nosuid. Make sure you do not have these flags set when mounting the file system for /var/cache/pbuilder or $BUILDPLACE.

This is not a problem when using user-mode-linux.

See 316135 for example.

21. pbuilder が遅い

pbuilder is often slow. The slowest part of pbuilder is extracting the tar.gz every time pbuilder is invoked. That can be avoided by using pbuilder-user-mode-linux. pbuilder-user-mode-linux uses the COW file system, and thus does not need to clean up and recreate the root file system.

pbuilder-user-mode-linux is slower in executing the actual build system, due to the usual user-mode-linux overhead for system calls. It is more friendly to the hard drive.

pbuilder with cowdancer is also an alternative that improves the speed of pbuilder startup.

22. Using pdebuild to sponsor package

To sign a package marking it for sponsorship, it is possible to use --auto-debsign and --debsign-k options of pdebuild.

	pdebuild  --auto-debsign  --debsign-k XXXXXXXX

23. Why is there a source.changes file in ../?

When running pdebuild, pbuilder will run dpkg-buildpackage to create a Debian source package to pass it on to pbuilder. A file named XXXX_YYY_source.changes is what remains from that process. It is harmless unless you try to upload it to the Debian archive.

This behavior is different when running through --use-pdebuild-internal

24. amd64 and i386-mode

amd64 architectures are capable of running binaries in i386 mode. It is possible to use pbuilder to run packages, using linux32 and the debootstrap --arch option. Specifically, a command-line option like the following will work.

pbuilder create --distribution sid --debootstrapopts --arch --debootstrapopts i386 \
  --basetgz /var/cache/pbuilder/base-i386.tgz --mirror http://deb.debian.org/debian
linux32 pbuilder build --basetgz /var/cache/pbuilder/base-i386.tgz

25. Using tmpfs for buildplace

To improve speed of operation, it is possible to use tmpfs for the pbuilder build location. Mount tmpfs to /var/cache/pbuilder/build, and set

APTCACHEHARDLINK=no

.

26. svn-buildpackage を pbuilder で利用する

The pdebuild command can be used with the svn-buildpackage --svn-builder command-line option: [8]

alias svn-cowbuilder="svn-buildpackage --svn-builder='pdebuild --pbuilder cowbuilder"


[6] This part of the documentation contributed by Andres Mejia.

This example was taken from a wiki (https://wiki.ubuntu.com/PbuilderHowto).

[7] Versions of bash from and before Debian 3.0.

第5章 Troubleshooting and development

1. Reporting bugs

To report bugs, it would be important to have a log of what's going wrong. Most of the time, adding a --debug option and re-running the session should do the trick. Please send the log of such a session along with your problem to ease the debugging process.

2. Mailing list

There is a mailing list for pbuilder on alioth (pbuilder-maint@lists.alioth.debian.org). You can subscribe through the alioth web interface: http://alioth.debian.org/mail/?group_id=30778.

3. IRC Channel

For coordination and communication, IRC channel #pbuilder on irc.oftc.net is used. Please log your intent there when you are going to start doing some changes and committing some change.

4. Information for pbuilder developers

This section tries to document current development practices and how things generally operate in development.

pbuilder is co-maintained with resources provided by Alioth. There is an Alioth project page at http://alioth.debian.org/projects/pbuilder. A home page is also available, at http://alioth.debian.org/projects/pbuilder, which shows this text. A git repository is available through http, git, or (if you have an account on alioth, ) ssh.

git-clone git://git.debian.org/git/pbuilder/pbuilder.git
git-clone http://git.debian.org/git/pbuilder/pbuilder.git
git-clone ssh://git.debian.org/git/pbuilder/pbuilder.git

Git commit message should have the first line describing what the commit does, formatted in the way debian/changelog is formatted because it is copied verbatim to changelog via git-dch. The second line is empty, and the rest should describe the background and extra information related to implementation of the commit.

Test-suites are available in the ./testsuite/ directory. Changes are expected not to break the test-suites. ./run-test.sh is a basic test-suite, which puts a summary in run-test.log, and run-test-cdebootstrap.log. ./run-test-regression.sh is a regression test-suite, which puts the result in run-test-regression.log. Currently, run-test.sh is run automatically daily to ensure that pbuilder is working.

表5.1 テストスイートのディレクトリ構造

ディレクトリ意味
./testsuite/Directory for testsuite.
./testsuite/run-test.shDaily regression test to test against Debian Archive changes breaking pbuilder.
./testsuite/run-test.logA summary of testsuite.
./testsuite/normal/Directory for testsuite results of running pbuilder with debootstrap.
./testsuite/cdebootstrap/Directory for testsuite results of running pbuilder with cdebootstrap.
./testsuite/run-regression.shRegression testsuite, run every time change is made to pbuilder to make sure there is no regression.
./testsuite/run-regression.logSummary of test result.
./testsuite/regression/BugID-*.shRegression tests, exit 0 for success, exit 1 for failure.
./testsuite/regression/BugID-*回帰テストスイートに利用されるファイル
./testsuite/regression/log/BugID-*.sh.logOutput of the regression test; output from the script is redirected by run-regression.sh.

When making changes, they should be documented in the Git commit log. git-dch will generate debian/changelog from the commit log. Make the first line of your commit log meaningful, and add any bug-closing information available. debian/changelog should not be edited directly except when releasing a new version.

A TODO file is available in debian/TODO. It's mostly not well-maintained, but hopefully it will be more up-to-date when people start using it. Emacs todoo-mode is used in editing the file.

When releasing a new version of pbuilder, the version is tagged with the git tag X.XXX (version number). This is done with the ./git-tag.sh script, available in the source tree.

第6章 Other uses of pbuilder

1. pbuilder を小規模な実験のために活用する

There are cases when some small amount of experimenting is required, and you do not want to damage the main system, like when installing experimental library packages, or compiling with experimental compilers. For such cases, the pbuilder login command is available.

pbuilder login is a debugging feature for pbuilder itself, but it also allows users to have a temporary chroot.

Note that the chroot is cleaned after logging out of the shell, and mounting file systems inside it is considered harmful.

2. Running little programs inside the chroot

To facilitate using pbuilder for other uses, pbuilder execute is available. pbuilder execute will take a script specified in the command-line argument, and invoke the script inside the chroot.

The script can be useful for sequences of operations such as installing ssh and adding a new user inside the chroot.

第7章 Experimental or wishlist features of pbuilder

There are some advanced features, above that of the basic feature of pbuilder, for some specific purposes.

1. LVMの活用

LVM2 has a useful snapshot function that features Copy-on-write images. That could be used for pbuilder just as it can be used for the user-mode-linux pbuilder port. The lvmpbuilder script in the examples directory implements such a port. The scripts and documentation can be found under /usr/share/doc/pbuilder/examples/lvmpbuilder/.

2. cowdancer の活用

cowdancer allows copy-on-write semantics on a file system using hard links and hard-link-breaking-on-write tricks. pbuilder using cowdancer seems to be much faster and it is one ideal point for improvement. cowbuilder, a wrapper for pbuilder that uses cowdancer, is available from the cowdancer package since version 0.14.

Example command-lines for cowbuilder look like the following:

# cowbuilder --create --distribution sid
# cowbuilder --update --distribution sid
# cowbuilder --build XXX.dsc

It is also possible to use cowdancer with the pdebuild command. Specify this with command-line option --pbuilder or set it in the PDEBUILD_PBUILDER configuration option.

$ pdebuild --pbuilder cowbuilder

3. tar.gz を利用しないで pbuilder を利用する

The --no-targz option of pbuilder will allow usage of pbuilder in a different way than conventional usage. It will try to use an existing chroot, and will not try to clean up after working on it. It is an operation mode more like sbuild.

It should be possible to create base chroot images for dchroot with the following commands:

# pbuilder create --distribution lenny --no-targz --basetgz /chroot/lenny
# pbuilder create --distribution squeeze --no-targz --basetgz /chroot/squeeze
# pbuilder create --distribution sid --no-targz --basetgz /chroot/sid

4. pbuilder を vserver で利用する

It is possible to use pbuilder in a vserver environment. This requires either vserver-patches in version 2.1.1-rc14 or higher, or a Linux kernel version 2.6.16 or higher.

To use pbuilder in a vserver, you need to set the secure_mount CAPS in the ccapabilities of this vserver.

5. Usage of ccache

It is possible to use the C compiler cache ccache to speed up repeated builds of the same package (or packages that compile the same files multiple times for some reason). Using ccache can speed up repeated building of large packages dramatically, at the cost of some disk space and bookkeeping.

To enable usage of ccache with pbuilder, you should set CCACHEDIR in your pbuilderrc file.

Current implementation of ccache support has several bugs, such that CCACHEDIR must be owned by the pbuilder build user, and parallel runs of pbuilder are not supported. Therefore it is not enabled by default.

第8章 参考文献

1. chroot 外部のディレクトリ構造

表8.1 chroot 内部のディレクトリ構造

ディレクトリ意味
/etc/pbuilderrcConfiguration file.
/usr/share/pbuilder/pbuilderrcDefault configuration.
/var/cache/pbuilder/base.tgzDefault location pbuilder uses for base.tgz, the tar-ball containing a basic Debian installation with only the build-essential packages.
/var/cache/pbuilder/build/PID/Default location pbuilder uses for chroot.
/var/cache/pbuilder/aptcacheDefault location pbuilder will use as apt cache, to store deb packages required during pbuilder build.
/var/cache/pbuilder/ccacheDefault location pbuilder will use as cache location.
/var/cache/pbuilder/resultDefault location where pbuilder puts the deb files and other files created after build.
/var/cache/pbuilder/pbuilder-umlresultDefault location where pbuilder-user-mode-linux puts the deb files and other files created after build.
/var/cache/pbuilder/pbuilder-mntDefault location pbuilder-user-mode-linux uses for mounting the COW file system, for chrooting.
/tmppbuilder-user-mode-linux will mount tmpfs for work.
${HOME}/tmp/PID.cowpbuilder-user-mode-linux uses this directory for location of COW file system.
${HOME}/uml-imagepbuilder-user-mode-linux uses this directory for user-mode-linux full disk image.

2. chroot 内部のディレクトリ構造

表8.2 chroot 内部のディレクトリ構造

ディレクトリ意味
/etc/mtab Symlink to /proc/mounts.
/tmp/builddDefault place used in pbuilder to place the Debian package to be processed. /tmp/buildd/packagename-version/ will be the root directory of the package being processed. HOME environment variable is set to this value inside chroot by pbuilder-buildpackage. --inputfile will place files here.
/runscriptThe script passed as an argument to pbuilder execute is passed on.
/tmp/hooks フックの場所。
/var/cache/apt/archives pbuilder copies the content of this directory to and from the aptcache directory located outside chroot.
/var/cache/pbuilder/ccache pbuilder bind-mounts this directory for use by ccache.
/tmp/XXXXpbuilder-user-mode-linux uses a script in /tmp to bootstrap into user-mode-linux.

第9章 些細な過去の経緯の詳細

1. マニュアルの履歴

This document was started on 28 Dec 2002 by Junichi Uekawa, trying to document what is known about pbuilder.

This documentation is available from the pbuilder source tar-ball, and from the git repository of pbuilder (web-based access is possible). A copy of this documentation can be found on the Alioth project page for pbuilder. There is also a PDF version. The homepage for pbuilder is http://pbuilder.alioth.debian.org/, hosted by the alioth project.

Documentation is written using DocBook XML, with emacs PSGML mode, and using wysidocbookxml for live previewing.

2. Possibly inaccurate Background History of pbuilder

The following is a most possibly inaccurate account of how pbuilder came to happen, and other attempts to make something like pbuilder happen. This part of the document was originally in the AUTHORS file, to give credit to those who existed before pbuilder.

2.1. The Time Before pbuilder

There was once dbuild, which was a shell script to build Debian packages from source. Lars Wirzenius wrote that script, and it was good, short, and simple (probably). There was nothing like build-depends then (I think), and it was simple. It might have been improved; I could only find references and no actual source.

debbuild was probably written by James Troup. I don't know because I have never seen the actual code; I could only find some references to it on the net, and mailing list logs.

sbuild is a perl script to build Debian packages from source. It parses Build-Depends, and performs other miscellaneous checks, and has a lot of hacks to actually get things building, including a table of what package to use when virtual packages are specified (does it do that still?). It supports the use of a local database for packages that do not have build-dependencies. It was written by Ronan Hodek, and I think it was patched and fixed and extended by several people. It is part of wanna-build, and used extensively in the Debian buildd system. I think it was maintained mostly by Ryan Murray.

2.2. pbuilder の誕生

wanna-build (sbuild) was (at the time of year 2001) quite difficult to set up, and it was never a Debian package. dbuild was something that predated Build-Depends.

Building packages from source using Build-Depends information within a chroot sounded trivial; and pbuilder was born. It was initially a shell script with only a few lines, which called debootstrap and chroot and dpkg-buildpackage in the same run, but soon, it was decided that that's too slow.

Yes, and it took almost a year to get things somewhat right, and in the middle of the process, Debian 3.0 was released. Yay. Debian 3.0 wasn't completely buildable with pbuilder, but the amount of packages which are not buildable is steadily decreasing (I hope).

2.3. そして二年目の人生

Someone wanted pbuilder to not run as root, and as User-mode-linux has become more useful as time passed, I've started experimenting with pbuilder-user-mode-linux. pbuilder-user-mode-linux has not stayed functional as much as I would have liked, and bootstrapping the user-mode-linux environment has been pretty hard, due to the quality of user-mode-linux code or packaging at that time, which kept on breaking network support in one way or the other.

2.4. pbuilder の5年目

pbuilder is now widely adopted as an 'almost standard' tool for testing packages, and building packages in a pristine environment. There are other, similar tools that do similar tasks, but they do not share the exact same goal. To commemorate this fact, pbuilder is now co-maintained by several people.

sbuild is now a well-maintained Debian package within Debian, and with pbuilder being such a slow monster, some people prefer the approach of sbuild. Development to use LVM-snapshots, cowloop, or cowdancer are hoped to improve the situation somewhat.