Rebuilding a Debian package

[gdt]

Build environment

$ sudo apt-get install build-essential devscripts fakeroot

Fetch source

This is three files: a .dsc, a debian.tar.gz and a .tar.gz.

There are a few ways to do this.

1)

$ apt-get source openssl

2)

$ dget http://security.debian.org/debian-security/pool/updates/main/o/openssl/openssl_1.0.1e-2+deb7u5.dsc

dget is in the devscripts package, which has a tonne of dependencies (such as installing a SMTP mail system).

3)

$ wget http://security.debian.org/debian-security/pool/updates/main/o/openssl/openssl_1.0.1e-2+deb7u5.dsc
$ wget http://security.debian.org/debian-security/pool/updates/main/o/openssl/openssl_1.0.1e-2+deb7u5.debian.tar.gz
$ wget http://security.debian.org/debian-security/pool/updates/main/o/openssl/openssl_1.0.1e.orig.tar.gz

Unpack the source and apply patches with:

$ dpkg-source -x openssl_1.0.1e-2+deb7u5.dsc
$ cd openssl-1.0.1e

Fetch build dependencies

1) The simplest way

$ sudo apt-get build-dep openssl

2) Otherwise look for Build-Requires lines in the file debian/control and install them individually:

$ sudo apt-get install debhelper m4 bc zlib1g-dev dpkg-dev

Build

There are multiple ways to do this.

1) The most basic is:

$ dpkg-buildpackage -us -uc -b

2) Debuild adds various checking of the resulting .deb (debuild is in the devscripts package):

$ debuild -us -uc -b

3) Pbuilder does the build in a clean environment, giving the best result (pbuilder is in the pbuilder package):

$ pbuilder --create
$ pbuilder --update
$ pbuilder --build --debbuildopts '-us -uc -b'