On Wed, Jul 30, 2014 at 11:30:39PM +0200, Václav Ovsík wrote: > Hi Peter, > thanks you for your attention on the ustr packaging. My work on ustr is > a bit stuck for some time. One reason is that upstream has no activity > for some time (great work of James Antill without bugs fortunately), the > other is I tried to prepare cross-build chroot (sbuild) without much > success. I'm not educated on cross-building yet :(. Can you direct me > how you are cross-building ustr please? Is it possible without Ubuntu > packages on current Debian Unstable? > Thanks for all patches. I will look at these after some brain restoration > :). I forgot almost everything...
Sure, no problem, it happens :) (I've had this happen quite a few times with both Debian and FreeBSD packages that I'm supposed to maintain, but haven't touched in years) Now, about the cross-build environment: the truth is, this was my first serious foray into cross-building, too :) However, the task was made much, much easier than usual by Helmut Grohne's rebootstrap tool - its very purpose is to, well, bootstrap the Debian archive on a new architecture, starting from scratch, zero host packages, building several cross-compilers, libc packages and other supporting packages first, and then building "normal" packages, one by one, in the order necessary to satisfy build dependencies, applying local patches as necessary. I'd recommend that you try it that way, too. The easiest way to install it does involve Ubuntu-related packages, but they are all in the Debian archive now, so this shouldn't be a problem. 1. Install the schroot, sbuild, and ubuntu-dev-tools packages. 2. Set up an 'sbuild' group and make your account a member; log out and then back in again if necessary for this to take effect. 3. Create a ~/.sbuildrc file from the example template at /usr/share/doc/sbuild/examples/example.sbuildrc I've attached mine, just as an example. 4. Run 'mk-sbuild' to create the master chroot which will be used for rebootstrap runs. The mk-sbuild defaults are fine, you mostly need to provide a name for the chroot (I use "rebootstrap" for mine) and, if necessary, the URL of the Debian mirror to use for the initial debootstrap run. I usually do something like: mk-sbuild --name=rebootstrap-demo --debootstrap-mirror=http://127.0.0.1:9999/debian/ unstable This points at my local approx instance as a Debian mirror. 5. Edit the schroot definition to allow members of the sbuild group to log in to the source chroot, not just create temp ones from it: sudo vim /etc/schroot/chroot.d/sbuild-rebootstrap-demo-amd64 Uncomment the source-root-users and source-root-groups lines. 6. Log into the source chroot to set it up for rebootstrap runs: schroot -c source:rebootstrap-demo-amd64 -u root 7. Set Apt up to skip recommended packages: echo 'APT { Install-Recommends: "false"; };' > /etc/apt/apt.conf.d/99local 8. Either install Git and then check out rebootstrap, or check out rebootstrap in a directory outside the master chroot and then copy it inside the chroot. If you choose to install Git inside the chroot: apt-get install git git clone git.debian.org:/git/users/helmutg/rebootstrap.git If you choose to clone rebootstrap outside the chroot, then you need to copy it inside the chroot afterwards; something like: sudo rsync -av rebootstrap/ /var/lib/schroot/mount/rebootstrap-demo-amd64-de4ba356-103e-4d9b-9ad4-49a85de1dc1e/root/rebootstrap/ Of course, your schroot session ID (the directory under /var/lib/schroot/mount/) will almost certainly be different; you can look it up inside the chroot by: printenv SCHROOT_SESSION_ID or printenv | fgrep SCHROOT Any way you choose (Git checkout inside the chroot or rsync/copy from outside), you should now have a /root/rebootstrap/ directory inside your current source chroot session. 9. Log out of the source chroot; your changes should be saved. exit 10. Create a temporary chroot from this template to actually run rebootstrap and cross-build something: schroot -c rebootstrap-demo-amd64 -u root cd rebootstrap 11. Pick an architecture that you want to cross-build for, pick a Debian mirror for rebootstrap to use, and, well, let it rip :) sh bootstrap.sh HOST_ARCH=armel MIRROR=http://127.0.0.1:9999/debian/ 2>&1 | tee /tmp/bootstrap.log 12. Now sit back and relax, or (from outside the chroot) monitor rebootstrap's progress by something like the attached script that extracts some of the info from the in-chroot /tmp/bootstrap.log: watch -n5 sh check-progress.sh rebootstrap-demo-amd64-c9563936-cd8a-41a3-9400-6ca1f92afca2 The result of the rebootstrap script will be twofold: there is a /tmp/result directory in the chroot that holds the built packages, and there is a reprepro Debian package repository in /tmp/repo (again, in the chroot) that, well, holds the built packages in an easier-to-use format :) The way I use those packages is to wait for something to show up in the repository, then rsync it (from outside the chroot) to a similar location in another chroot, then install packages from it. There are two types of packages there: native ones (pretty much only the cross-compiler) and host ones (the actual cross-built ones for your target architecture). Note that to install host packages for cross-building and keep a clean environment you may need to do something similar to what rebootstrap does with dpkg and the sources.list file: 1. Let dpkg know you're interested in the host architecture, too: dpkg --add-architecture armel 2. Edit /etc/apt/sources.list and, well, pretty much all of your /etc/apt/ources.list.d/* files and add the "[ arch-=armel ]" notation after each "deb" line, so that apt never tries to fetch host packages from the Debian archive; they may not be there at all (if the architecutre has not been properly bootstrapped yet, or if it is only in debian-ports, or if something is wrong and you're trying to diagnose it by doing the cross-building yourself) or, in theory, they might not be completely compatible with the rebootstrap-built ones. 3. Edit /etc/apt/sources.list or add an /etc/apt/sources.list.d/ file pointing at the rsynced /tmp/repo reprepro repository, so that apt knows it can fetch packages for the host architecture from it. 4. Install the cross-compiler: apt-cache search -n gcc-4.9-arm apt-get install gcc-4.9-arm-linux-gnueabi (you may have to answer 'yes' to the unauthenticated packages prompt, unless you've taken the trouble to actually sign the packages built by rebootstrap) Then go into /usr/bin/ and, well, create some missing symlinks: cd /usr/bin for src in *-4.9; do dst="${src%-4.9}"; if [ -f "$src" ] && [ ! -f "$dst" ]; then ln -sv "$src" "$dst"; fi; done 5. Get the source and the build dependencies of the package that you intend to cross-build (in this case, ustr): mkdir /tmp/build cd /tmp/build apt-get source ustr cd ustr*/ apt-get build-dep ustr apt-get build-dep -aarmel --arch-only ustr In the case of ustr, the last command will do nothing, since ustr does not have any arch-dependent build dependencies - it only build-depends on debhelper and cdbs, and those are both arch-independent, so the native versions (installed by the simple "apt-get build-dep ustr") will serve just fine. 6. Try to cross-build the package, specifying the host architecture: dpkg-buildpackage -aarmel -uc -us Now, in the unpatched ustr case, this will actually almost succeed - right up to the point at the end where dh_strip tries to run the armel "strip" cross-tool on the just-built ustr binaries. It will fail with a "File format not recognized" error, because... well, beccause ustr's upstream Makefile hard-codes the C compiler name to "cc", it doesn't listen to the debian/rules file, which can supply a cross-compiler name, so even though we pass "-aarmel" to dpkg-buildpackage, it doesn't affect the ustr build at all! :) So... 7. Apply the patches and try to cross-build ustr again :) (copy the patches from outside the chroot into the chroot's /tmp/build/ ) debian/rules clean export QUILT_PATCHES=debian/patches qiult pop -a quilt push -a quilt import -p1 -Pdebian/config-compile.diff ../config-compile.diff quilt import -p1 -Pdebian/cross-build.diff ../cross-build.diff quilt pop -a And now try it again: debian/rules clean dpkg-buildpackage -aarmel -uc -us Right, this one will fail again, since we forgot one of the basic rules of cross-building: "no running host programs" usually implies "disable the test suite, please!" But we can already check that something good happened: file libustr-1.0.so.1.0.4 libustr-1.0.so.1.0.4: ELF 32-bit LSB shared object, ARM, EABI5 version 1 (SYSV), dynamically linked, BuildID[sha1]=117fbf898f5d5c50b6a6902ceac037eff880c399, not stripped So here we go again: debian/rules clean env DEB_BUILD_OPTIONS=nocheck dpkg-buildpackage -aarmel -uc -us And there you go :) OK, so it wasn't quite simple, but, well, I do believe this is still one of the simplest ways to create a cross-build environment from scratch on a recent Debian system. Here's hoping that this didn't scare you too much, and here's hoping that it actually helped :) G'luck, Peter -- Peter Pentchev [email protected] [email protected] [email protected] PGP key: http://people.FreeBSD.org/~roam/roam.key.asc Key fingerprint 2EE7 A7A5 17FC 124C F115 C354 651E EFB0 2527 DF13
# *** VERIFY AND UPDATE $mailto and $maintainer_name BELOW *** # Mail address where logs are sent to (mandatory, no default!) $mailto = 'roam'; # Name to use as override in .changes files for the Maintainer: field #$maintainer_name='roam <roam@localhost>'; # Directory for chroot symlinks and sbuild logs. Defaults to the # current directory if unspecified. #$build_dir='/home/roam/ubuntu/build'; # Directory for writing build logs to $log_dir="/var/lib/sbuild/logs"; # APT_DISTUPGRADE # Type: BOOL # APT distupgrade. 1 to enable running "apt-get dist-upgrade" at the start # of each build, or 0 to disable. $apt_distupgrade = 0; # APT_UPDATE # Type: BOOL # APT update. 1 to enable running "apt-get update" at the start of each # build, or 0 to disable. $apt_update = 0; # CHROOT # Type: STRING # Default chroot (defaults to distribution[-arch][-sbuild]) $chroot = 'unstable-amd64'; # don't remove this, Perl needs it: 1;
check-progress.sh
Description: Bourne shell script
signature.asc
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