X-Git-Url: https://git.hcoop.net/jackhill/guix/guix.git/blobdiff_plain/f8348b91adf7c878ffad2229e60db7c67565a516..eeba7d3a076d0a9ed168c500d13afdb129199e56:/HACKING diff --git a/HACKING b/HACKING dissimilarity index 95% index b6b9b462f9..20cc9ea6ea 100644 --- a/HACKING +++ b/HACKING @@ -1,163 +1,63 @@ --*- mode: org; coding: utf-8; -*- - -#+TITLE: Hacking GNU Guix and its incredible distro - -Copyright © 2012 Ludovic Courtès - - Copying and distribution of this file, with or without modification, - are permitted in any medium without royalty provided the copyright - notice and this notice are preserved. - - -* Adding new packages - -Package recipes in Guix look like this: - -#+BEGIN_SRC scheme - (package - (name "nettle") - (version "2.5") - (source - (origin - (method http-fetch) - (uri (string-append "http://ftp.gnu.org/gnu/nettle/nettle-" - version ".tar.gz")) - (sha256 - (base32 - "0wicr7amx01l03rm0pzgr1qvw3f9blaw17vjsy1301dh13ll58aa")))) - (build-system gnu-build-system) - (inputs `(("gnum4" ,gnum4))) - (propagated-inputs `(("gmp" ,gmp))) - (home-page - "http://www.lysator.liu.se/~nisse/nettle/") - (synopsis "GNU Nettle, a cryptographic library") - (description - "Nettle is a cryptographic library...") - (license "GPLv2+")) -#+END_SRC - -Such a recipe can be written by hand, and then tested by running -‘./pre-inst-env guix-build nettle’. - -When writing the recipe, the base32-encoded SHA256 hash of the source -code tarball, which can be seen in the example above, can be obtained by -running: - - guix-download http://ftp.gnu.org/gnu/nettle/nettle-2.5.tar.gz - -Alternatively, it is possible to semi-automatically import recipes from -the [[http://nixos.org/nixpkgs/][Nixpkgs]] software distribution using this command: - - guix-import /path/to/nixpkgs/checkout nettle - -The command automatically fetches and converts to Guix the “Nix -expression” of Nettle. - -* Porting the Guix distro on a new platform - -** Introduction - -Unlike Make or similar build tools, Guix requires absolutely /all/ the -dependencies of a build process to be specified. - -For a user-land software distribution, that means that the process that -builds GCC (then used to build all other programs) must itself be -specified; and the process to build the C library to build that GCC; and -the process to build the GCC to build that library; and... See the -problem? Chicken-and-egg. - -To break that cycle, the distro starts from a set of pre-built -binaries–usually referred to as “bootstrap binaries.” These include -statically-linked versions of Guile, GCC, Coreutils, Make, Grep, sed, -etc., and the GNU C Library. - -This section describes how to build those bootstrap binaries when -porting to a new platform. - -** When the platform is supported by Nixpkgs - -In that case, the easiest thing is to bootstrap the distro using -binaries from Nixpkgs. - -To do that, you need to comment out the definitions of -‘%bootstrap-guile’ and ‘%bootstrap-inputs’ in distro/packages/bootstrap.scm -to force the use of Nixpkgs derivations. For instance, when porting to -‘i686-linux’, you should redefine these variables along these lines: - -#+BEGIN_SRC scheme - (define %bootstrap-guile - (nixpkgs-derivation "guile" "i686-linux")) - - (define %bootstrap-inputs - (compile-time-value - `(("libc" ,(nixpkgs-derivation "glibc" "i686-linux")) - ,@(map (lambda (name) - (list name (nixpkgs-derivation name "i686-linux"))) - '("gnutar" "gzip" "bzip2" "xz" "patch" - "coreutils" "gnused" "gnugrep" "bash" - "gawk" ; used by `config.status' - "gcc" "binutils"))))) -#+END_SRC - -That should allow the distro to be bootstrapped. - -Then, the tarballs containing the initial binaries of Guile, Coreutils, -GCC, libc, etc. need to be built. To that end, run the following -commands: - -#+BEGIN_SRC sh - ./pre-inst-env guix-build \ - -e '(@@ (distro packages base) %guile-bootstrap-tarball)' \ - --system=i686-linux - - ./pre-inst-env guix-build \ - -e '(@@ (distro packages base) %bootstrap-binaries-tarball)' \ - --system=i686-linux - - ./pre-inst-env guix-build \ - -e '(@@ (distro packages base) %binutils-bootstrap-tarball)' \ - --system=i686-linux - - ./pre-inst-env guix-build \ - -e '(@@ (distro packages base) %glibc-bootstrap-tarball)' \ - --system=i686-linux - - ./pre-inst-env guix-build \ - -e '(@@ (distro packages base) %gcc-bootstrap-tarball)' \ - --system=i686-linux - -#+END_SRC - -These should build tarballs containing statically-linked tools usable on -that system. - -In the source tree, you need to install binaries for ‘mkdir’, ‘bash’, -‘tar’, and ‘xz’ under ‘distro/packages/bootstrap/i686-linux’. These -binaries can be extracted from the static-binaries tarball built above. - -A rule for -‘distro/packages/bootstrap/i686-linux/guile-bootstrap-2.0.6.tar.xz’ -needs to be added in ‘Makefile.am’, with the appropriate hexadecimal -vrepresentation of its SHA256 hash. - -You may then revert your changes to ‘base.scm’. For the variables -‘%bootstrap-coreutils&co’, ‘%bootstrap-binutils’, ‘%bootstrap-glibc’, -and ‘%bootstrap-gcc’, the expected SHA256 of the corresponding tarballs -for ‘i686-linux’ (built above) must be added. - -This should be enough to bootstrap the distro without resorting to -Nixpkgs. - -** When the platform is *not* supported by Nixpkgs - -In that case, the bootstrap binaries should be built using whatever -tools are available on the target platform. That is, the tarballs and -binaries show above must first be built manually, using the available -tools. - -They should have the same properties as those built by the Guix recipes -shown above. For example, all the binaries (except for glibc) must be -statically-linked; the bootstrap Guile must be relocatable (see patch in -the Guix distro); the static-binaries tarball must contain the same -programs (Coreutils, Grep, sed, Awk, etc.); and so on. - +-*- mode: org; coding: utf-8; -*- + +#+TITLE: Hacking GNU Guix and Its Incredible Distro + +Copyright © 2012, 2013, 2014, 2016, 2017 Ludovic Courtès +Copyright © 2015, 2017 Mathieu Lirzin +Copyright © 2017 Leo Famulari + + Copying and distribution of this file, with or without modification, + are permitted in any medium without royalty provided the copyright + notice and this notice are preserved. + +* Contributing + +See the manual for useful hacking informations, either by running + + info -f doc/guix.info "Contributing" + +or by checking the [[http://www.gnu.org/software/guix/manual/guix.html#Contributing][web copy of the manual]]. + +* Commit Access + +For frequent contributors, having write access to the repository is +convenient. When you deem it necessary, feel free to ask for it on the +mailing list. When you get commit access, please make sure to follow the +policy below (discussions of the policy can take place on guix-devel@gnu.org.) + +Non-trivial patches should always be posted to guix-patches@gnu.org (trivial +patches include fixing typos, etc.) This mailing list fills the +patch-tracking database at [[https://bugs.gnu.org/guix-patches]]; see +"Contributing" in the manual for details. + +For patches that just add a new package, and a simple one, it’s OK to commit, +if you’re confident (which means you successfully built it in a chroot setup, +and have done a reasonable copyright and license auditing.) Likewise for +package upgrades, except upgrades that trigger a lot of rebuilds (for example, +upgrading GnuTLS or GLib.) We have a mailing list for commit notifications +(guix-commits@gnu.org), so people can notice. Before pushing your changes, +make sure to run ‘git pull --rebase’. + +All commits that are pushed to the central repository on Savannah must be +signed with an OpenPGP key, and the public key should be uploaded to your user +account on Savannah and to public key servers, such as ‘pgp.mit.edu’. To +configure Git to automatically sign commits, run: + + git config commit.gpgsign true + git config user.signingkey CABBA6EA1DC0FF33 + +You can prevent yourself from accidentally pushing unsigned commits to +Savannah by using the pre-push Git hook called located at ‘etc/git/pre-push’: + + cp etc/git/pre-push .git/hooks/pre-push + +When pushing a commit on behalf of somebody else, please add a Signed-off-by +line at the end of the commit log message (e.g. with ‘git am --signoff’). +This improves tracking of who did what. + +For anything else, please post to guix-patches@gnu.org and leave time for a +review, without committing anything. If you didn’t receive any reply +after two weeks, and if you’re confident, it’s OK to commit. + +That last part is subject to being adjusted, allowing individuals to commit +directly on non-controversial changes on parts they’re familiar with.