NAME¶
germinate
—
expand dependencies in a list of seed packages
SYNOPSIS¶
germinate |
[ -v ]
[-S
source ]
[-s
dist ]
[-m
mirror ]
[-d
dist,... ]
[-a
arch ]
[-c
component,... ]
[- -bzr ]
[- -no-rdepends ]
[- -no-installer ] |
DESCRIPTION¶
germinate
is a program to help with the
maintenance of large software distributions. It takes a list of seed packages
and a mirror of the distribution, and produces outputs with the seed packages
and their dependencies and build-dependencies expanded out in full.
Seeds¶
The contents of the Ubuntu distribution, and others, are managed by means of
seeds. At their simplest, these are lists of
packages which are considered important to have in the main component of the
distribution, without explicitly listing all their dependencies and
build-dependencies.
Seed lists are typically divided up by category: a
base
or
minimal
seed might list the core set of packages
required to make the system run at all, while a
desktop
seed might list the set of packages installed
as part of a default desktop installation.
germinate
takes these seeds, adds their
dependency trees, and produces an
output for each
seed which contains a dependency-expanded list of package names. These outputs
may be handed on to archive maintenance or CD-building tools.
Some seeds may
inherit from other seeds: they rely
on those seeds to be installed. For example, a
desktop
seed will typically inherit from a
minimal
seed.
germinate
understands these inheritance
relationships. If a package in the
desktop
seed
depends on ‘foo’, but ‘foo’ is already part of the
minimal
seed or dependency list, then
‘foo’ will not be added to the
desktop
output.
Seeds are stored in text files downloaded from a given URL. Lines not beginning
with ‘ * ’ (wiki-style list markup) are ignored.
Seed entries may simply consist of a package name, or may include any of the
following special syntax:
- %
- Seed entries beginning with ‘%’ expand to all binaries from
the given source package.
- [...]
- Seed entries may be followed with ‘
[arch1 arch2
...]’ to indicate that they should only be used on the given
architectures, or with ‘ [!arch1
!arch2 ...]’ to indicate that they
should not be used on the given architectures.
- (...)
- Seed entries in parentheses indicate that the seed should be treated as a
recommendation of metapackages generated from this seed, rather than as a
dependency.
- !
- Seed entries beginning with ‘!’ cause the given package to
be blacklisted from the given seed and any seeds from which it inherits;
this may be followed by ‘%’ as above to blacklist all
binaries from the given source package. Note that this may result in
uninstallable packages whose dependencies have been blacklisted, so use
this feature sparingly. The purpose of a blacklist is to make it obvious
when a package that is not supposed to be installed ends up in
germinate
's output, so that package
relationships can be fixed to stop that happening. It is not intended for
the purpose of working around buggy package relationships, and attempts to
do so will not work because apt
has no
way to know about blacklist entries in seeds.
- key: value
- Some seeds also contain headers at the top of the file, in “key:
value” format. For the most part, these are not parsed by
germinate
itself. The Ubuntu
tasksel
package uses keys beginning
with ‘Task-’ to define fields of similar names in its
.desc files.
germinate-update-metapackage(1) uses some of
these headers to reduce the need for fragile configuration; see its
documentation for further details.
A
STRUCTURE file alongside the seeds lists
their inheritance relationships. It may also include lines beginning with
‘include’, causing other collections of seeds to be included as
if they were part of the collection currently being germinated, or lines
beginning with ‘feature’, which set flags for the processing of
seeds. The only flag currently defined is ‘follow-recommends’,
which causes
germinate
to treat Recommends
fields as if they were Depends. (Features may also be set on a per-seed basis
using lines beginning with ‘ * Feature:’ in the
seed file; here, ‘no-follow-recommends’ is also supported to
allow Recommends-following to be turned off for individual seeds.)
Build-dependencies and ‘supported’¶
There is typically no need for a default desktop installation to contain all the
compilers and development libraries needed to build itself from source; if
nothing else, it would consume much more space. Nevertheless, it is normally a
requirement for the maintainers of a distribution to support all the packages
necessary to build that distribution.
germinate
therefore does not add all the
packages that result from following build-dependencies of seed packages and of
their dependencies (the “build-dependency tree”) to every
output, unless they are also in the seed or in the dependency list. Instead,
it adds them to the output for the last seed in the
STRUCTURE file, conventionally called
supported
.
Like any other seed, the supported seed may contain its own list of packages. It
is common to provide support for many software packages which are not in the
default installation, such as debugging libraries, optimised kernels,
alternative language support, and the like.
Outputs¶
The output files are named after the seed to which they correspond. An
additional output file is needed for supported, namely
‘supported+build-depends’, which contains the supported list and
the build-depends lists of the other seeds all joined together. An
‘all’ output is produced to represent the entire archive.
Some other files are produced for occasional use by experts. See the
README file for full details on these.
OPTIONS¶
-v
,
-
-verbose
- Be more verbose when processing seeds.
-S
,
-
-seed-source
source,...
- Fetch seeds from the specified sources. The default is
http://people.canonical.com/~ubuntu-archive/seeds/,
or
http://bazaar.launchpad.net/~ubuntu-core-dev/ubuntu-seeds/
if the
-
-bzr
option is used. You may use file://
URLs here to fetch seeds from the local file system; for example, if your
seeds are stored in
/home/username/seeds/debian.unstable,
then you would use the options -S
file:///home/username/seeds/
-s
debian.unstable.
-s
,
-
-seed-dist
dist
- Fetch seeds for distribution dist. The
default is
ubuntu.trusty
.
-m
,
-
-mirror
mirror
- Get package lists from mirror. The
default is
http://archive.ubuntu.com/ubuntu/. May
be supplied multiple times; the newest version of each package across all
archives will win.
-
-source-mirror
mirror
- Get source package lists from mirror. The
default is to use package lists mirrors. May be supplied multiple times;
the newest version of each source package across all archives will
win.
-d
,
-
-dist
dist,...
- Operate on the specified distributions. The default is
trusty
. Listing multiple distributions may be
useful, for example, when examining both a released distribution and its
security updates.
-a
,
-
-arch
arch
- Operate on architecture arch. The default
is
i386
.
-c
,
-
-components
component,...
- Operate on the specified components. The default is
main
.
-
-bzr
- Check out seeds from the
bzr
branch
found at
seed-source/seed-dist
rather than fetching them directly from a URL. Requires
bzr
to be installed.
-
-no-rdepends
- Disable reverse-dependency calculations. These calculations cause a large
number of small files to be written out in the
rdepends/ directory, and may take some
time.
-
-no-installer
- Do not consider debian-installer udeb packages. While generally not the
desired outcome, sometimes you might wish to omit consideration of
installer packages when processing your seeds, perhaps if sending the
output directly to the package manager on an already-installed
system.
-
-seed-packages
parent/pkg,...
- Treat each pkg as a seed by itself,
inheriting from parent (i.e. assuming
that all packages in the parent seed are
already installed while calculating the additional dependencies of
pkg). This allows the use of
germinate
to calculate the dependencies
of individual extra packages. For example,
-
-seed-packages
desktop/epiphany-browser
will create an epiphany-browser output
file listing the additional packages that need to be installed over and
above the desktop seed in order to
install epiphany-browser.
BUGS¶
The wiki-style markup in seeds was inherited from an early implementation, and
is a wart.
germinate
can sometimes be confused by
complicated situations involving the order in which it encounters dependencies
on virtual packages. Explicit entries in seeds may be required to work around
this.
Handling of installer packages (udebs) is complicated, poorly documented, and
doesn't always work quite right: in particular, packages aren't demoted to the
supported seed when they should be.
AUTHORS¶
Scott James Remnant
⟨scott@canonical.com⟩
Colin Watson
⟨cjwatson@canonical.com⟩
germinate
is copyright © 2004, 2005,
2006, 2007, 2008
Canonical Ltd. See the GNU
General Public License version 2 or later for copying conditions. A copy of
the GNU General Public License is available in
/usr/share/common-licenses/GPL.