Know it
Ever needed to downgrade a Debian package that has versioned dependencies? I
have. plan-downgrade.pl is a script to make my life
easier - it can find a set of packages needed for a downgrade.
plan-downgrade.pl has two modes of operation: version dependency finder and
snapshot timestamp resolver. Dependency finder finds versioned packages that
are needed for downgrade. This is the default mode. Snapshot timestamp resolver
can be used to find Debian snapshot archive timestamp for requested version and
to list all available version for a package.
Note that you’re using this script at your own risk. It worked for me when I wanted to downgrade X.org, but it may not work for your use case. If it breaks your installation, you get to keep both pieces. Think before you act and know what you’re doing.
This script is written in Perl and it depends on a few (Debian) packages. Obviously it depends on Perl, but also on the following.
- libapt-pkg-perl (developed with 0.1.25)
- libwww-curl-perl (developed with 4.15-1+b1)
Get it
Use it
perl plan-downgrade.pl PACKAGE=VERSION ...
perl plan-downgrade.pl --find-snapshots PACKAGE=VERSION ...
Basically, downgrading a Debian package is trivial. All you need is a package
name and version. Unfortunately, in real life things may not be as
straightforward. Naturally you’ll need the old packages, either from local
cache or from a repository. Debian snapshot
archive can help with old packages, but you’ll
still have to worry about versioned dependencies as apt-get nor aptitude take
care of this for you. This is where plan-downgrade.pl steps in.
Here’s an example of plan-downgrade.pl in action the way I use it. In reality
I downgraded to 2:1.10.4-1, but I didn’t want to upgrade to the latest just to
be able to make a real-life example here. Note that I use mixture of aptitude
and apt-get. This way I don’t mark downgraded packages as manually installed
for aptitude.
% perl plan-downgrade.pl --find-snapshots xserver-xorg-core=2:1.9.5-1
Using architecture: amd64
Package: xserver-xorg-core
Retrieving available versions for xserver-xorg-core...
Retrieving timestamps for xserver-xorg-core=2:1.9.5-1...
Snapshot repositories:
20110326T085552Z http://snapshot.debian.org/archive/debian/20110326T085552Z/
[edit /etc/apt/sources.list.d/snapshot.list]
% sudo aptitude -o Acquire::Check-Valid-Until=false update
[snip]
% sudo apt-get -V install $(perl plan-downgrade.pl xserver-xorg-core=2:1.9.5-1)
Investigating xserver-xorg-core=2:1.9.5-1...
Investigating xserver-xorg-video-voodoo=1:1.2.4-2...
Investigating xserver-xorg-video-vmware=1:11.0.3-2...
Investigating xserver-xorg-video-vesa=1:2.3.0-5...
Investigating xserver-xorg-video-tseng=1:1.2.4-2...
Investigating xserver-xorg-video-trident=1:1.3.4-2...
Investigating xserver-xorg-video-tdfx=1:1.4.3-4...
Investigating xserver-xorg-video-sisusb=1:0.9.4-2...
Investigating xserver-xorg-video-sis=1:0.10.3-3...
Investigating xserver-xorg-video-siliconmotion=1:1.7.5-1...
Investigating xserver-xorg-video-savage=1:2.3.2-3...
Investigating xserver-xorg-video-s3=1:0.6.3-4...
Investigating xserver-xorg-video-rendition=1:4.2.4-2...
Investigating xserver-xorg-video-r128=6.8.1-5...
Investigating xserver-xorg-video-openchrome=1:0.2.904+svn916-3...
Investigating xserver-xorg-video-neomagic=1:1.2.5-2...
Investigating xserver-xorg-video-mach64=6.8.2-5...
Investigating xserver-xorg-video-intel=2:2.14.0-4...
Investigating xserver-xorg-video-i128=1:1.3.4-2...
Investigating xserver-xorg-video-glint=1:1.2.5-2...
Investigating xserver-xorg-video-fbdev=1:0.4.2-4...
Investigating xserver-xorg-video-dummy=1:0.3.4-2...
Investigating xserver-xorg-video-cirrus=1:1.3.2-4...
Investigating xserver-xorg-video-radeon=1:6.14.0-1...
Investigating xserver-xorg-input-mouse=1:1.7.0-1...
Investigating xserver-xorg-input-kbd=1:1.6.0-1...
Investigating xserver-xorg-input-evdev=1:2.6.0-2...
Investigating xserver-xorg=1:7.6+4...
Investigating xserver-xorg=1:7.6+8...
Investigating xserver-xorg-video-nvidia=285.05.09-1...
Investigating nvidia-glx=285.05.09-1...
Reading package lists... Done
Building dependency tree
Reading state information... Done
nvidia-glx is already the newest version.
xserver-xorg-video-nvidia is already the newest version.
xserver-xorg is already the newest version.
The following extra packages will be installed:
libxcb-aux0 (0.3.6-1)
Suggested packages:
xfonts-scalable (1.0.3-1)
firmware-linux (0.33)
Recommended packages:
libgl1-mesa-dri (7.11-6)
The following NEW packages will be installed:
libxcb-aux0 (0.3.6-1)
The following packages will be DOWNGRADED:
xserver-xorg-core (1.10.4-1 => 1.9.5-1)
xserver-xorg-input-evdev (2.6.0-2+b1 => 2.6.0-2)
xserver-xorg-input-kbd (1.6.0-3 => 1.6.0-1)
xserver-xorg-input-mouse (1.7.1-1 => 1.7.0-1)
xserver-xorg-video-cirrus (1.3.2-4+b1 => 1.3.2-4)
xserver-xorg-video-dummy (0.3.4-2+b1 => 0.3.4-2)
xserver-xorg-video-fbdev (0.4.2-4+b1 => 0.4.2-4)
xserver-xorg-video-glint (1.2.5-2+b1 => 1.2.5-2)
xserver-xorg-video-i128 (1.3.4-2+b1 => 1.3.4-2)
xserver-xorg-video-intel (2.15.0-3 => 2.14.0-4)
xserver-xorg-video-mach64 (6.9.0-1 => 6.8.2-5)
xserver-xorg-video-neomagic (1.2.5-2+b1 => 1.2.5-2)
xserver-xorg-video-openchrome (0.2.904+svn920-1 => 0.2.904+svn916-3)
xserver-xorg-video-r128 (6.8.1-5+b1 => 6.8.1-5)
xserver-xorg-video-radeon (6.14.2-1 => 6.14.0-1)
xserver-xorg-video-rendition (4.2.4-2+b1 => 4.2.4-2)
xserver-xorg-video-s3 (0.6.3-4+b1 => 0.6.3-4)
xserver-xorg-video-savage (2.3.2-3+b1 => 2.3.2-3)
xserver-xorg-video-siliconmotion (1.7.5-1+b1 => 1.7.5-1)
xserver-xorg-video-sis (0.10.3-3+b1 => 0.10.3-3)
xserver-xorg-video-sisusb (0.9.4-2+b1 => 0.9.4-2)
xserver-xorg-video-tdfx (1.4.3-4+b1 => 1.4.3-4)
xserver-xorg-video-trident (1.3.4-2+b1 => 1.3.4-2)
xserver-xorg-video-tseng (1.2.4-2+b1 => 1.2.4-2)
xserver-xorg-video-vesa (2.3.0-7 => 2.3.0-5)
xserver-xorg-video-vmware (11.0.3-2+b1 => 11.0.3-2)
xserver-xorg-video-voodoo (1.2.4-2+b1 => 1.2.4-2)
0 upgraded, 1 newly installed, 27 downgraded, 0 to remove and 107 not upgraded.
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