Last year I'd described my setup of a local network-buildd using pbuilder, ccache, inoticoming and NFS. One then-still-open goal was to support different Debian releases. This is especially necessary for backports of e.g. bluefish. The rules to contribute backports require to include all changelog entries since the last version on debian-backports or since stable if it's the first version
in an uploaded package. Therefor one needs to know the last version in e.g. wheezy-backports. Because I'm not typing the command (the source package only gets uploaded and inoticoming starts the build process) I was looking for a way to automatically retrieve that version and add the relevant -vX.Y-Z switch to dpkg-buildpackage.
The solution I found requires aptitude and a sources.list entry for the relevant release. If you are only interested in the solution, just jump to the end :)
I'm going to add the version switch to the DEBBUILDOPTS variable of pbuilder. In my setup I have a common (shared) snippet called /etc/pbuilderrc.inc and one configuration file per release and architecture, say /etc/pbuilderrc.amd64.stable. Now the first already contains ...
DEBBUILDOPTS="-us -uc -j2"
... and DEBBUILDOPTS can be extended in the latter:
DEBBUILDOPTS+="..."
Because the config file is parsed pretty early in the process the package name has not yet been assigned to any variable. The last argument to pbuilder is the .dsc file. So I use the last argument and parse the file to retrieve the source package name.
cat ${@: -1} | grep -e ^Source | awk -F\ '{ print $2 }'
The solution above works, because pbuilder is a BASH script. Otherwise it maybe needs some tweaking. I use the source package name, because it is unique and there is just one :) Now with this name I check for all versions in wheezy* and stable* and sort them. The sort order of aptitude is from low to high, so the last line shopuld contain the highest version. This covers the possibility that there has not yet been a backport or that there is one:
aptitude versions -F '%p' --show-package-names=never --group-by=none --sort=version \ "?narrow(?source-package(^PACKAGE\$), ?or(?archive(^wheezy.*), ?archive(^stable.*)))" |\ tail -n 1 | sed -e 's#~bpo.*$##g'
The sed-part is necessary because otherwise dh_genchanges will add a superfluous changelog entry (the last one of the last upload). To make things easier, I assign the name and version to variables. So this is the complete solution:
[..]
MYPACKAGE="`cat ${@: -1} | grep -e ^Source | awk -F\ '{ print $2 }'`"
MYBPOVERS="`aptitude versions -F '%p' --show-package-names=never --group-by=none --sort=version "?narrow(?source-package(^$MYPACKAGE\$), ?or(?archive(^wheezy.*), ?archive(^stable.*)))" | tail -n 1 | sed -e 's#~bpo.*$##g'`"
log "I: Package is $MYPACKAGE and last stable/bpo version is $MYBPOVERS"
DEBBUILDOPTS+=" -v$MYBPOVERS"
[..]
Examples
I've recently built a new bluefish backport. The last backport version is 2.2.6-1~bpo70+1. There is also the stable version 2.2.3-4. So the version I need is 2.2.6-1 (2.2.6-1~bpo70+1 < 2.2.6-1!!). Checking the log it works:
I: Package is bluefish and last stable/bpo version is 2.2.6-1
A different example is rsync. I've recently locally rebuilt it for a stable system (wanted to make use of the --chown switch). There is not yet a backport. So the version I (would) need is 3.0.9-4. Checking the logs again and works too:
I: Package is rsync and last stable/bpo version is 3.0.9-4
Feedback appreciated ...
