4.5 KiB
NOTE THIS STUFF IS OUT OF DATE! I'm working on merging some of these ideas into jhbuild for now.
== The recipe set ==
A recipe is similar to Bitbake's format, except just have metadata - we don't allow arbitrary Python scripts. Also, we assume autotools. Example:
SUMMARY = "The basic file, shell and text manipulation utilities."
HOMEPAGE = "http://www.gnu.org/software/coreutils/"
BUGTRACKER = "http://debbugs.gnu.org/coreutils"
LICENSE = "GPLv3+"
LIC_FILES_CHKSUM = "file://COPYING;md5=d32239bcb673463ab874e80d47fae504
file://src/ls.c;startline=5;endline=16;md5=e1a509558876db58fb6667ba140137ad"
SRC_URI = "${GNU_MIRROR}/coreutils/${BP}.tar.gz
file://remove-usr-local-lib-from-m4.patch
"
DEPENDS = "gmp foo"
Each recipe will output one or more artifacts.
In GNOME, we will have a root per:
- major version (3.0, 3.2)
- "runtime", "sdk", and "devel"
- Build type (opt, debug)
- Architecture (ia32, x86_64)
/gnome/root-3.2-runtime-opt-x86_64/{etc,bin,share,usr,lib} /gnome/root-3.2-devel-debug-x86_64/{etc,bin,share,usr,lib} /gnome/.real/root-3.2-runtime-opt-x86_64 /gnome/.real/root-3.2-devel-debug-x86_64
A "runtime" root is what's necessary to run applications. A SDK root is that, plus all the command line developer tools (gcc, gdb, make, strace). And finally the "devel" root has all the API-unstable headers not necessary for applications (NetworkManager.h etc.)
Hmm, maybe we should punt developer tools into a Unix app framework.
== Artifact ==
An artifact is a binary result of compiling a recipe (there may be multiple). Think of an artifact as like a Linux distribution "package", except there are no runtime dependencies, conflicts, or pre/post scripts. It's basically just a gzipped tarball, and we encode metadata in the filename.
Example:
gdk-pixbuf-runtime,o=master,r=3.2-opt-x86_64,b=opt,v=2.24.0-10-g1d39095,.tar.gz
This is an artifact from the gdk-pixbuf component. Here's a decoding of the key/value pairs:
o: The origin of the build - there are just "master" and "local" r: The name of the root this artifact was compiled against b: The name of the build flavor (known values are "opt" and "debug") v: The output of "git describe".
To build a root, we simply unpack the artifacts that compose it, and run "git commit".
hacktree will default to splitting up shared libraries' unversioned .so link and header files into -devel, and the rest into -runtime.
All binaries default to runtime.
Local modifications ==
A key point of this whole endeavour is that we want developers to be able to do local builds. This is surprisingly something not well supported by the Debian/Fedora's tools at least.
=== Updating a root with a new local artifact ===
Whenever you install a local artifact, if no "local" branch exists for that root, it's created.
Let's say we're debugging gdk-pixbuf, tracking down a memory corruption bug. We've added a few printfs, and want to rerun things. GCC optimization is screwing us, so we build it in debug mode (-O0). The active root is root-3.2-opt.
$ pwd ~/src/gdk-pixbufroot $ echo $HACKTREE_ROOT /gnome/root-3.2-opt $ hacktree make debug <time passes, hopefully not too much> $ ls gdk-pixbuf*.tar.gz gdk-pixbuf-runtime,o=master,r=3.2-opt,b=debug,v=2.24.0-10-g1d39095,.tar.gz gdk-pixbuf-devel,o=master,r=3.2-opt,b=debug,v=2.24.0-10-g1d39095,.tar.gz gdk-pixbuf-manifests,o=master,r=3.2-opt,b=debug,v=2.24.0-10-g1d39095,.tar.gz $ hacktree install gdk-pixbuf*,o=master,r=3.2-opt,b=debug,v=2.24.0-10-g1d39095,.tar.gz
Now here's where the cool stuff happens. hacktree takes /gnome/root-3.2-opt (the which is given in the r= above), and looks for the corresponding git branch (root-3.2-opt). Now hacktree notices there's no corresponding "local" branch, i.e. local-3.2-opt. One is created and checked out:
pwd
/gnome/repo.git
git branch local-3.2-opt root-3.2-opt
git clone --branch local-3.2-opt /gnome/repo.git /gnome/.real-local-3.2-opt
Now, the artifacts specified are overlaid:
cd /gnome/.real-local-3.2-opt
tar xvf
Ok, now we need to remove old no longer shipped files from the root. Thus, we need a list of files corresponding to each original artifact, and to know which artifacts are in a root. Note above that one of the artifacts produced was "manifests". This contains files like:
/meta/manifests/gdk-pixbuf-runtime.list /meta/manifests/gdk-pixbuf-devel.list
Thus we diff the manifests, and clean up any leftover files.