From 3db3779b6a37c5682bf11a1801c66d9542b4d93f Mon Sep 17 00:00:00 2001
From: Johannes Schauer Marin Rodrigues <josch@mister-muffin.de>
Date: Mon, 16 Jan 2023 08:15:07 +0100
Subject: [PATCH] add hooks/maybe-jessie-or-older and hooks/maybe-merged-usr

---
 hooks/maybe-jessie-or-older/extract00.sh | 28 +++++++++++++++++++++
 hooks/maybe-jessie-or-older/extract01.sh | 31 ++++++++++++++++++++++++
 hooks/maybe-merged-usr/essential00.sh    | 25 +++++++++++++++++++
 hooks/maybe-merged-usr/setup00.sh        | 27 +++++++++++++++++++++
 4 files changed, 111 insertions(+)
 create mode 100755 hooks/maybe-jessie-or-older/extract00.sh
 create mode 100755 hooks/maybe-jessie-or-older/extract01.sh
 create mode 100755 hooks/maybe-merged-usr/essential00.sh
 create mode 100755 hooks/maybe-merged-usr/setup00.sh

diff --git a/hooks/maybe-jessie-or-older/extract00.sh b/hooks/maybe-jessie-or-older/extract00.sh
new file mode 100755
index 0000000..dbd3af8
--- /dev/null
+++ b/hooks/maybe-jessie-or-older/extract00.sh
@@ -0,0 +1,28 @@
+#!/bin/sh
+
+set -eu
+
+# if dpkg is new enough, do nothing
+# we cannot ask dpkg-query about the version because dpkg is only extracted
+# but not installed at this point
+dpkg_ver="$(chroot "$1" dpkg --version | grep --extended-regexp --only-matching '[0-9]+\.[0-9.]+')"
+if dpkg --compare-versions "$dpkg_ver" ge 1.17.11; then
+	echo "dpkg version $dpkg_ver is >= 1.17.11 -- not running jessie-or-older extract00 hook" >&2
+	exit 0
+else
+	echo "dpkg version $dpkg_ver is << 1.17.11 -- running jessie-or-older extract00 hook" >&2
+fi
+
+# resolve the script path using several methods in order:
+#  1. using dirname -- "$0"
+#  2. using ./hooks
+#  3. using /usr/share/mmdebstrap/hooks/
+for p in "$(dirname -- "$0")/.." ./hooks /usr/share/mmdebstrap/hooks; do
+	if [ -x "$p/jessie-or-older/extract00.sh" ] && [ -x "$p/jessie-or-older/extract01.sh" ]; then
+		"$p/jessie-or-older/extract00.sh" "$1"
+		exit 0
+	fi
+done
+
+echo "cannot find jessie-or-older hook anywhere" >&2
+exit 1
diff --git a/hooks/maybe-jessie-or-older/extract01.sh b/hooks/maybe-jessie-or-older/extract01.sh
new file mode 100755
index 0000000..1d26475
--- /dev/null
+++ b/hooks/maybe-jessie-or-older/extract01.sh
@@ -0,0 +1,31 @@
+#!/bin/sh
+
+set -eu
+
+# If the init package has not been extracted, then it is not part of the
+# Essential:yes set and we do not need this workaround. This holds true for the
+# init package version 1.34 and later. Instead of asking apt about the init
+# version (which might not be the same version that was picked to be installed)
+# we check for the presence of the init package by checking whether
+# /usr/share/doc/init/copyright exists.
+
+if [ -e "$1/usr/share/doc/init/copyright" ]; then
+	echo "the init package is not Essential:yes -- not running jessie-or-older extract01 hook" >&2
+	exit 0
+else
+	echo "the init package is Essential:yes -- running jessie-or-older extract01 hook" >&2
+fi
+
+# resolve the script path using several methods in order:
+#  1. using dirname -- "$0"
+#  2. using ./hooks
+#  3. using /usr/share/mmdebstrap/hooks/
+for p in "$(dirname -- "$0")/.." ./hooks /usr/share/mmdebstrap/hooks; do
+	if [ -x "$p/jessie-or-older/extract00.sh" ] && [ -x "$p/jessie-or-older/extract01.sh" ]; then
+		"$p/jessie-or-older/extract01.sh" "$1"
+		exit 0
+	fi
+done
+
+echo "cannot find jessie-or-older hook anywhere" >&2
+exit 1
diff --git a/hooks/maybe-merged-usr/essential00.sh b/hooks/maybe-merged-usr/essential00.sh
new file mode 100755
index 0000000..e7f9c6c
--- /dev/null
+++ b/hooks/maybe-merged-usr/essential00.sh
@@ -0,0 +1,25 @@
+#!/bin/sh
+
+set -eu
+
+# if the usr-is-merged package cannot be installed with apt, do nothing
+if ! env --chdir="$1" APT_CONFIG="$MMDEBSTRAP_APT_CONFIG" apt-cache show --no-all-versions usr-is-merged > /dev/null 2>&1; then
+	echo "no package called usr-is-merged found -- not running merged-usr essential hook" >&2
+	exit 0
+else
+	echo "package usr-is-merged found -- running merged-usr essential hook" >&2
+fi
+
+# resolve the script path using several methods in order:
+#  1. using dirname -- "$0"
+#  2. using ./hooks
+#  3. using /usr/share/mmdebstrap/hooks/
+for p in "$(dirname -- "$0")/.." ./hooks /usr/share/mmdebstrap/hooks; do
+	if [ -x "$p/merged-usr/setup00.sh" ] && [ -x "$p/merged-usr/essential00.sh" ]; then
+		"$p/merged-usr/essential00.sh" "$1"
+		exit 0
+	fi
+done
+
+echo "cannot find merged-usr hook anywhere" >&2
+exit 1
diff --git a/hooks/maybe-merged-usr/setup00.sh b/hooks/maybe-merged-usr/setup00.sh
new file mode 100755
index 0000000..56afc13
--- /dev/null
+++ b/hooks/maybe-merged-usr/setup00.sh
@@ -0,0 +1,27 @@
+#!/bin/sh
+
+set -eu
+
+env --chdir="$1" APT_CONFIG="$MMDEBSTRAP_APT_CONFIG" apt-get update --error-on=any
+
+# if the usr-is-merged package cannot be installed with apt, do nothing
+if ! env --chdir="$1" APT_CONFIG="$MMDEBSTRAP_APT_CONFIG" apt-cache show --no-all-versions usr-is-merged > /dev/null 2>&1; then
+	echo "no package called usr-is-merged found -- not running merged-usr setup hook" >&2
+	exit 0
+else
+	echo "package usr-is-merged found -- running merged-usr setup hook" >&2
+fi
+
+# resolve the script path using several methods in order:
+#  1. using dirname -- "$0"
+#  2. using ./hooks
+#  3. using /usr/share/mmdebstrap/hooks/
+for p in "$(dirname -- "$0")/.." ./hooks /usr/share/mmdebstrap/hooks; do
+	if [ -x "$p/merged-usr/setup00.sh" ] && [ -x "$p/merged-usr/essential00.sh" ]; then
+		"$p/merged-usr/setup00.sh" "$1"
+		exit 0
+	fi
+done
+
+echo "cannot find merged-usr hook anywhere" >&2
+exit 1