1 files changed, 83 insertions, 0 deletions
diff --git a/debian/apt.auto-removal.sh b/debian/apt.auto-removal.sh
new file mode 100644
index 0000000..2c32b0c
--- /dev/null
+++ b/debian/apt.auto-removal.sh
@@ -0,0 +1,83 @@
+#!/bin/sh
+set -e
+# Mark as not-for-autoremoval those kernel packages that are:
+#  - the currently booted version
+#  - the kernel version we've been called for
+#  - the latest kernel version (as determined by debian version number)
+#  - the second-latest kernel version
+#
+# In the common case this results in two kernels saved (booted into the
+# second-latest kernel, we install the latest kernel in an upgrade), but
+# can save up to four. Kernel refers here to a distinct release, which can
+# potentially be installed in multiple flavours counting as one kernel.
+
+eval $(apt-config shell APT_CONF_D Dir::Etc::parts/d)
+test -n "${APT_CONF_D}" || APT_CONF_D="/etc/apt/apt.conf.d"
+config_file="${APT_CONF_D}/01autoremove-kernels"
+
+eval $(apt-config shell DPKG Dir::bin::dpkg/f)
+test -n "$DPKG" || DPKG="/usr/bin/dpkg"
+
+list="$("${DPKG}" -l | awk '/^[ih][^nc][ ]+(linux|kfreebsd|gnumach)-image-[0-9]+\./ && $2 !~ /-dbg(:.*)?$/ && $2 !~ /-dbgsym(:.*)?$/ { print $2,$3; }' \
+   | sed -e 's#^\(linux\|kfreebsd\|gnumach\)-image-##' -e 's#:[^:]\+ # #')"
+debverlist="$(echo "$list" | cut -d' ' -f 2 | sort --unique --reverse --version-sort)"
+
+if [ -n "$1" ]; then
+	installed_version="$(echo "$list" | awk "\$1 == \"$1\" { print \$2;exit; }")"
+fi
+unamer="$(uname -r | tr '[A-Z]' '[a-z]')"
+if [ -n "$unamer" ]; then
+	running_version="$(echo "$list" | awk "\$1 == \"$unamer\" { print \$2;exit; }")"
+fi
+# ignore the currently running version if attempting a reproducible build
+if [ -n "${SOURCE_DATE_EPOCH}" ]; then
+	unamer=""
+	running_version=""
+fi
+latest_version="$(echo "$debverlist" | sed -n 1p)"
+previous_version="$(echo "$debverlist" | sed -n 2p)"
+
+debkernels="$(echo "$latest_version
+$installed_version
+$running_version
+$previous_version" | sort -u | sed -e '/^$/ d')"
+kernels="$( (echo "$1
+$unamer"; for deb in $debkernels; do echo "$list" | awk "\$2 == \"$deb\" { print \$1; }"; done; ) \
+   | sed -e 's#\([\.\+]\)#\\\1#g' -e '/^$/ d' | sort -u)"
+
+generateconfig() {
+	cat <<EOF
+// DO NOT EDIT! File autogenerated by $0
+APT::NeverAutoRemove
+{
+EOF
+	for package in $(apt-config dump --no-empty --format '%v%n' 'APT::VersionedKernelPackages'); do
+		for kernel in $kernels; do
+			echo "   \"^${package}-${kernel}$\";"
+		done
+	done
+	echo '};'
+	if [ "${APT_AUTO_REMOVAL_KERNELS_DEBUG:-true}" = 'true' ]; then
+		cat <<EOF
+/* Debug information:
+# dpkg list:
+$(dpkg -l | grep '\(linux\|kfreebsd\|gnumach\)-image-')
+# list of installed kernel packages:
+$list
+# list of different kernel versions:
+$debverlist
+# Installing kernel: $installed_version ($1)
+# Running kernel: ${running_version:-ignored} (${unamer:-ignored})
+# Last kernel: $latest_version
+# Previous kernel: $previous_version
+# Kernel versions list to keep:
+$debkernels
+# Kernel packages (version part) to protect:
+$kernels
+*/
+EOF
+	fi
+}
+generateconfig "$@" > "${config_file}.dpkg-new"
+mv -f "${config_file}.dpkg-new" "$config_file"
+chmod 444 "$config_file"