* Added lb_chroot_layered to add support for multi layered squashfs images

* auto/*: Added live-layered image format

live-build/auto/build

@@ -254,7 +254,11 @@ rm -f /usr/sbin/update-initramfs
 dpkg-divert --quiet --remove --rename /usr/sbin/update-initramfs
 EOF
 
-	lb chroot "$@"
+	if [ "${IMAGEFORMAT:-}" = live-layered ]; then
+		PATH="config/:$PATH" lb chroot_layered "$@"
+	else
+		lb chroot "$@"
+	fi
 
 	if [ "${SUBPROJECT:-}" = minimized ]; then
 		# force removal of initramfs-tools, which we assert is not
@@ -474,6 +478,28 @@ EOF
 	/usr/share/livecd-rootfs/minimize-manual chroot
 
 	lb binary "$@"
+
+	# Create layered squashfs system
+	if [ "${IMAGEFORMAT:-}" = live-layered ]; then
+		for _PASS in $PASSES
+		do
+			squashfs_f="${PWD}/livecd.${PROJECT}.${_PASS}.squashfs"
+
+			(cd "chroot.${_PASS}/" &&
+      			mksquashfs . ${squashfs_f} \
+        		-no-progress -xattrs -comp xz )
+
+			squashfs_f_manifest="${squashfs_f}.manifest"
+			create_manifest "chroot.${_PASS}/" "${squashfs_f_manifest}"
+		done
+		# We are skipping lb_binary_rootfs
+	fi
+
+	# Teardown mount points in layered mode
+	if [ -x config/teardown_chroot_layered ]; then
+		config/teardown_chroot_layered
+	fi
+
 	touch binary.success
 ) 2>&1 | tee binary.log
 

live-build/auto/clean

@@ -8,3 +8,4 @@ rm -rf config
 rm -f binary.manifest binary.manifest-desktop binary.log
 rm -f livecd.*
 rm -rf userdata
+rm -rf chroot.*

live-build/auto/config

@@ -33,6 +33,7 @@ fi
 
 mkdir -p config
 cp -af /usr/share/livecd-rootfs/live-build/functions config/functions
+cp -af /usr/share/livecd-rootfs/live-build/lb_chroot_layered config/lb_chroot_layered
 cp -af /usr/share/livecd-rootfs/live-build/snap-seed-parse.py config/snap-seed-parse
 
 mkdir -p config/package-lists
@@ -69,6 +70,9 @@ add_binary_hook ()
 }
 
 if [ -z "${IMAGEFORMAT:-}" ]; then
+	if [ ${SUBPROJECT:-} = layered ]; then
+		IMAGEFORMAT=live-layered
+	fi
 	case $PROJECT:${SUBPROJECT:-} in
 		ubuntu-cpc:*)
 			if [ "$SUBARCH" = "raspi3" ]; then
@@ -189,6 +193,12 @@ case $IMAGEFORMAT in
 		exit 0
 		;;
 
+	live-layered)
+		# Stop lb creating filesystem.squashfs by skipping lb_binary_rootfs and lb_binary_manifest
+		skip_lb_stage binary_rootfs
+		skip_lb_stage binary_manifest
+		;;
+
 	none)
 		OPTS="${OPTS:+$OPTS }--chroot-filesystem $IMAGEFORMAT"
 		;;
@@ -321,8 +331,19 @@ esac
 
 case $PROJECT in
 	ubuntu|ubuntu-dvd)
-		add_task install minimal standard ubuntu-desktop
+		case ${SUBPROJECT:-} in
-		LIVE_TASK='ubuntu-live'
+			layered)
+				PASSES="install-minimal install live"
+				add_task install-minimal minimal standard
+				add_task install ubuntu-desktop
+				LIVE_TASK='ubuntu-live'
+				;;
+			*)
+				add_task install minimal standard ubuntu-desktop
+				LIVE_TASK='ubuntu-live'
+				;;
+		esac
+
 		case $ARCH in
 			amd64)	add_package live $SIGNED_KERNEL_PACKAGE ;;
 		esac
@@ -686,54 +707,56 @@ case $SUBPROJECT in
 		;;
 esac
 
-# we'll expand the base seed given here according to the STRUCTURE file, and
+if [ "${IMAGEFORMAT:-}" != live-layered ]; then
-# then look in all of the seeds found to see which snaps are seeded
+	# we'll expand the base seed given here according to the STRUCTURE file, and
-case $PROJECT:${SUBPROJECT:-} in
+	# then look in all of the seeds found to see which snaps are seeded
-	ubuntu:*|kubuntu*:*|lubuntu*:*|xubuntu*:*|ubuntu-mate*:*|ubuntustudio*:*|ubuntukylin*:*|ubuntu-budgie*:*)
+	case $PROJECT:${SUBPROJECT:-} in
-		BASE_SEED='desktop'
+		ubuntu:*|kubuntu*:*|lubuntu*:*|xubuntu*:*|ubuntu-mate*:*|ubuntustudio*:*|ubuntukylin*:*|ubuntu-budgie*:*)
-		;;
+			BASE_SEED='desktop'
-	ubuntu-cpc:*)
+			;;
-		BASE_SEED='server'
+		ubuntu-cpc:*)
-		;;
+			BASE_SEED='server'
-	ubuntu-server:live)
+			;;
-		BASE_SEED='server'
+		ubuntu-server:live)
-		# subiquity is seeded but in a separate squashfs via hooks; set HOOK_SNAPS and ALL_SNAPS.
+			BASE_SEED='server'
-		HOOK_SNAPS='subiquity'
+			# subiquity is seeded but in a separate squashfs via hooks; set HOOK_SNAPS and ALL_SNAPS.
-		ALL_SNAPS=''
+			HOOK_SNAPS='subiquity'
-		;;
+			ALL_SNAPS=''
-esac
+			;;
+	esac
 
-if [ -n "${BASE_SEED}" ]; then
+	if [ -n "${BASE_SEED}" ]; then
-	SEEDS_EXPANDED=$(inheritance ${BASE_SEED})
+		SEEDS_EXPANDED=$(inheritance ${BASE_SEED})
-	for seed in ${SEEDS_EXPANDED}; do
+		for seed in ${SEEDS_EXPANDED}; do
-		echo "snap: considering ${seed}"
+			echo "snap: considering ${seed}"
-		file=config/germinate-output/${seed}.snaps
+			file=config/germinate-output/${seed}.snaps
-		[ -e "${file}" ] || continue
+			[ -e "${file}" ] || continue
-		# extract the first column (snap package name) from germinate's output
+			# extract the first column (snap package name) from germinate's output
-		# translate the human-readable "foo (classic)" into a
+			# translate the human-readable "foo (classic)" into a
-		# more machine readable "foo/classic"
+			# more machine readable "foo/classic"
-		seed_snaps=$(sed -rn '1,/-----/d;/-----/,$d; s/(.*) \|.*/\1/; s, \(classic\),/classic,; p' "${file}")
+			seed_snaps=$(sed -rn '1,/-----/d;/-----/,$d; s/(.*) \|.*/\1/; s, \(classic\),/classic,; p' "${file}")
-		for snap in ${seed_snaps}; do
+			for snap in ${seed_snaps}; do
-			echo "snap: found ${snap}"
+				echo "snap: found ${snap}"
-			ALL_SNAPS="${ALL_SNAPS:+${ALL_SNAPS} }${snap}"
+				ALL_SNAPS="${ALL_SNAPS:+${ALL_SNAPS} }${snap}"
+			done
 		done
-	done
+		if [ -n "${ALL_SNAPS}" ] || [ -n "${HOOK_SNAPS}" ]; then
-	if [ -n "${ALL_SNAPS}" ] || [ -n "${HOOK_SNAPS}" ]; then
+			echo "${ALL_SNAPS}" > config/seeded-snaps
-		echo "${ALL_SNAPS}" > config/seeded-snaps
+		fi
 	fi
-fi
 
-# grab a list of packags to remove for a "minimal" installation from the seed
+	# grab a list of packags to remove for a "minimal" installation from the seed
-# mirror for this project
+	# mirror for this project
-if [ -n "${BASE_SEED}" ] && [ -n "${BASE_SEED}" ]; then
+	if [ -n "${BASE_SEED}" ] && [ -n "${BASE_SEED}" ]; then
-	minimal_packages_url=${SEEDMIRROR}/${SEED}/${BASE_SEED}.minimal-remove
+		minimal_packages_url=${SEEDMIRROR}/${SEED}/${BASE_SEED}.minimal-remove
-	echo -n "Checking ${minimal_packages_url} for a minimal installation list... "
+		echo -n "Checking ${minimal_packages_url} for a minimal installation list... "
-	minimal_packages_remove=$(wget -q -O- ${minimal_packages_url} | sed -e '/\s*#.*$/d' -e '/^\s*$/d')
+		minimal_packages_remove=$(wget -q -O- ${minimal_packages_url} | sed -e '/\s*#.*$/d' -e '/^\s*$/d')
-	if [ -n "${minimal_packages_remove}" ]; then
+		if [ -n "${minimal_packages_remove}" ]; then
-		echo "${minimal_packages_remove}" > config/manifest-minimal-remove
+			echo "${minimal_packages_remove}" > config/manifest-minimal-remove
-		echo "$(echo ${minimal_packages_remove} | tr '\n' ' ')"
+			echo "$(echo ${minimal_packages_remove} | tr '\n' ' ')"
-	else
+		else
-		echo "failed to retrieve, not including."
+			echo "failed to retrieve, not including."
+		fi
 	fi
 fi
 
@@ -857,6 +880,10 @@ lb config noauto \
 echo "LB_CHROOT_HOOKS=\"$CHROOT_HOOKS\"" >> config/chroot
 echo "SUBPROJECT=\"${SUBPROJECT:-}\"" >> config/chroot
 echo "LB_DISTRIBUTION=\"$SUITE\"" >> config/chroot
+echo "IMAGEFORMAT=$IMAGEFORMAT" >> config/common
+if [ -n "$PASSES" ]; then
+	echo "PASSES=\"$PASSES\"" >> config/common
+fi
 echo "LB_BINARY_HOOKS=\"$BINARY_HOOKS\"" >> config/binary
 echo "BUILDSTAMP=\"$NOW\"" >> config/binary
 echo "SUBPROJECT=\"${SUBPROJECT:-}\"" >> config/binary

live-build/lb_chroot_layered

@@ -0,0 +1,141 @@
+#!/bin/sh
+
+## live-build(7) - System Build Scripts
+## Copyright (C) 2006-2012 Daniel Baumann <daniel@debian.org>
+##
+## This program comes with ABSOLUTELY NO WARRANTY; for details see COPYING.
+## This is free software, and you are welcome to redistribute it
+## under certain conditions; see COPYING for details.
+
+## This is a fork of lb_chroot for layered live system.
+## We don't want leaking host configuratino in each layer, and so,
+## we clean and setup the chroot each time.
+## In addition, we create the squashfs for each layer, but top one (live)
+## which still can be configured after lb chroot call.
+
+set -e
+
+# Including common functions
+( . "${LIVE_BUILD}/scripts/build.sh" > /dev/null 2>&1 || true ) || . /usr/lib/live/build.sh
+
+# Automatically populating config tree
+if [ -x auto/config ] && [ ! -e .build/config ]
+then
+	Echo_message "Automatically populating config tree."
+	lb config
+fi
+
+# Setting static variables
+DESCRIPTION="$(Echo 'customize the Debian system')"
+HELP=""
+USAGE="${PROGRAM} [--force]"
+
+Arguments "${@}"
+
+# Reading configuration files
+Read_conffiles config/all config/common config/bootstrap config/chroot config/binary config/source
+Set_defaults
+
+# Setup cleanup function
+Setup_cleanup
+
+. config/functions
+
+teardownPath="config/teardown_chroot_layered"
+cat >> $teardownPath << EOF
+#!/bin/sh
+set -e
+EOF
+chmod +x $teardownPath
+
+PASSES="${PASSES:-install live}"
+CURPASS=1
+LASTPASS=$(echo $PASSES|wc -w)
+for _PASS in $PASSES
+do
+
+	if [ $CURPASS -gt 1 ]; then
+		mkdir chroot.${_PASS}
+		mount_overlay chroot/ "chroot.${_PASS}/" chroot/
+		cat >> $teardownPath << EOF		
+umount chroot/
+EOF
+	fi
+
+	# Configuring chroot
+	lb chroot_cache restore ${*}
+	lb chroot_devpts install ${*}
+	lb chroot_proc install ${*}
+	lb chroot_selinuxfs install ${*}
+	lb chroot_sysfs install ${*}
+	lb chroot_debianchroot install ${*}
+	lb chroot_dpkg install ${*}
+	lb chroot_tmpfs install ${*}
+	lb chroot_sysv-rc install ${*}
+	lb chroot_upstart install ${*}
+	lb chroot_hosts install ${*}
+	lb chroot_resolv install ${*}
+	lb chroot_hostname install ${*}
+	lb chroot_apt install ${*}
+	lb chroot_archives chroot install ${*}
+
+	# Customizing chroot
+	lb chroot_linux-image ${*}
+	lb chroot_preseed ${*}
+	lb chroot_early_hooks ${*}
+
+	lb chroot_package-lists ${_PASS} ${*}
+	lb chroot_install-packages ${_PASS} ${*}
+
+	# Kernel should be in first layer
+	if [ $CURPASS -eq 1 ]; then
+		Chroot chroot "dpkg -l linux-headers-3* linux-headers-4*" 2>/dev/null \
+			| awk '/^i/ {print $2}' > chroot.headers
+		for i in $(cat chroot.headers); do
+			Chroot chroot "apt-mark auto $i"
+		done
+	fi
+
+	Chroot chroot "apt-get --purge -y autoremove"
+
+	# Add live packages to top layer
+	if [ $CURPASS -eq $LASTPASS ]; then
+		lb chroot_live-packages ${*}
+	fi
+
+	lb chroot_includes ${*}
+	# TODO: look if this is what copies distro hooks
+	lb chroot_hooks ${*}
+	lb chroot_hacks ${*}
+	lb chroot_interactive ${*}
+
+	Chroot chroot "dpkg-query -W" > chroot.packages.${_PASS}
+
+	# Deconfiguring chroot
+	lb chroot_archives chroot remove ${*}
+	lb chroot_apt remove ${*}
+	lb chroot_hostname remove ${*}
+	lb chroot_resolv remove ${*}
+	lb chroot_hosts remove ${*}
+	lb chroot_sysv-rc remove ${*}
+	lb chroot_upstart remove ${*}
+	lb chroot_tmpfs remove ${*}
+	lb chroot_dpkg remove ${*}
+	lb chroot_debianchroot remove ${*}
+	lb chroot_sysfs remove ${*}
+	lb chroot_selinuxfs remove ${*}
+	lb chroot_proc remove ${*}
+	lb chroot_devpts remove ${*}
+	lb chroot_cache save ${*}
+
+	if [ $CURPASS -eq 1 ]; then
+		cp -a chroot chroot.${_PASS}
+	fi
+	
+	CURPASS=$(( CURPASS + 1 ))
+done
+
+# Remove unused chroot binary corresponding to bottom layer (once everything is unmount)
+cat >> $teardownPath << EOF		
+rm -rf chroot/
+EOF