By passing an additional directory to run-parts, allow Debian and its derivatives an easy way to ship maintainer scripts in /usr while at the same time allowing the local admin to easily 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: 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 | 44 ++++++++++++++++++++++++++++++++-------- 1 file changed, 36 insertions(+), 8 deletions(-) diff --git a/scripts/package/builddeb b/scripts/package/builddeb index 441b0bb66e0d..2772146a76ce 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 +93,26 @@ 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" || exit 0 + + # If more than one hook directory remained, check version of run-parts. If + # run-parts is too old, fall back to only processing the first. + case \$hookdirs in *" "*) if ! run-parts --help 2>&1 \ + | grep -Fxq "Usage: run-parts [OPTION]... DIRECTORY [DIRECTORY ...]"; then + echo "E: run-parts >=5.21 is required for multiple hook directories, falling back to $firsthookdir" >&2 + test -d "${firsthookdir}/${script}.d" || exit 0 + hookdirs="${firsthookdir}/${script}.d" + fi + esac + run-parts --arg="${KERNELRELEASE}" --arg="/${installed_image_path}" \$hookdirs exit 0 EOF chmod 755 "${pdir}/DEBIAN/${script}" -- 2.39.2
