By passing an additional directory to run-parts, allow Debian and its derivatives to ship maintainer scripts in /usr while at the same time allowing the local admin to override or disable them by placing hooks of the same name in /etc. This adds support for the mechanism described in the UAPI Configuration Files Specification for kernel hooks. The same idea is also used by udev, systemd or modprobe for their config files. https://uapi-group.org/specifications/specs/configuration_files_specification/ This functionality relies on run-parts 5.21 or later. It is the responsibility of packages installing hooks into /usr/share/kernel to also declare a Depends: debianutils (>= 5.21). KDEB_HOOKDIR can be used to change the list of directories that is searched. By default, /etc/kernel and /usr/share/kernel are hook directories. Signed-off-by: Johannes Schauer Marin Rodrigues <josch@xxxxxxxxxxxxxxxx> --- scripts/package/builddeb | 33 +++++++++++++++++++++++++-------- 1 file changed, 25 insertions(+), 8 deletions(-) diff --git a/scripts/package/builddeb b/scripts/package/builddeb index 441b0bb66e0d..6e83f6f3ec6d 100755 --- a/scripts/package/builddeb +++ b/scripts/package/builddeb @@ -5,10 +5,12 @@ # # Simple script to generate a deb package for a Linux kernel. All the # complexity of what to do with a kernel after it is installed or removed -# is left to other scripts and packages: they can install scripts in the -# /etc/kernel/{pre,post}{inst,rm}.d/ directories (or an alternative location -# specified in KDEB_HOOKDIR) that will be called on package install and -# removal. +# is left to other scripts and packages. Scripts can be placed into the +# preinst, postinst, prerm and postrm directories in /etc/kernel or +# /usr/share/kernel. A different list of search directories can be given +# via KDEB_HOOKDIR. Scripts in directories earlier in the list will +# override scripts of the same name in later directories. The script will +# be called on package installation and removal. set -eu @@ -68,11 +70,18 @@ install_linux_image () { # kernel packages, as well as kernel packages built using make-kpkg. # make-kpkg sets $INITRD to indicate whether an initramfs is wanted, and # so do we; recent versions of dracut and initramfs-tools will obey this. - debhookdir=${KDEB_HOOKDIR:-/etc/kernel} + debhookdir=${KDEB_HOOKDIR:-/etc/kernel /usr/share/kernel} + + # Only pre-create the first hook directory. Support for more than one hook + # directory requires run-parts 5.21 and it is the responsibility of packages + # creating additional hook directories to declare that dependency. + firsthookdir=${debhookdir%% *} for script in postinst postrm preinst prerm; do - mkdir -p "${pdir}${debhookdir}/${script}.d" + mkdir -p "${pdir}${firsthookdir}/${script}.d" + done - mkdir -p "${pdir}/DEBIAN" + mkdir -p "${pdir}/DEBIAN" + for script in postinst postrm preinst prerm; do cat <<-EOF > "${pdir}/DEBIAN/${script}" #!/bin/sh @@ -84,7 +93,15 @@ install_linux_image () { # Tell initramfs builder whether it's wanted export INITRD=$(if_enabled_echo CONFIG_BLK_DEV_INITRD Yes No) - test -d ${debhookdir}/${script}.d && run-parts --arg="${KERNELRELEASE}" --arg="/${installed_image_path}" ${debhookdir}/${script}.d + # run-parts will error out if one of its directory arguments does not + # exist, so filter the list of hook directories accordingly. + hookdirs= + for dir in ${debhookdir}; do + test -d "\$dir/${script}.d" || continue + hookdirs="\$hookdirs \$dir/${script}.d" + done + hookdirs="\${hookdirs# }" + test -n "\$hookdirs" && run-parts --arg="${KERNELRELEASE}" --arg="/${installed_image_path}" \$hookdirs exit 0 EOF chmod 755 "${pdir}/DEBIAN/${script}" -- 2.39.2
