pacwrap/bin/pachwrap-create

#!/bin/bash
#
#  Pachwrap -- chroot initialisation utility
# 
#  Copyright (C) 2023 Xavier R.M. 
#  sapphirus(at)azorium(dot)net
#
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation, with only version 3 of the License.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program.  If not, see <https://www.gnu.org/licenses/>.

MACHINE_ID=$(cat /dev/urandom | tr -dc 'a-z0-9' | fold -w 32 | head -n 1)
EXEC_NAME="pachwrap-create" 
EXEC_SCRIPT="pachwrap-exec"

main () {	

	parse_args "$@"

	if [[ $SWITCH == *v* ]]; then
		VER_DISPLAY=$EXEC_NAME chpak -v
		exit
	fi

	if [[ ! $SANDBOX ]]; then
		echo $EXEC_NAME": Sandbox not specified."
		exit 1
	fi

	init_vars

	if [[ -d $INSTANCE_ROOT ]] || [[ -d $INSTANCE_HOME ]]; then 
		echo $EXEC_NAME": Root or home directory for $SANDBOX exists. Aborting." 
		exit 1
	fi

	if [[ ! -d $BASE_ROOT ]] && [[ ! $DEPEND ]]; then
		echo $EXEC_NAME": Directory not found for $DEPEND root dependency."
		exit 1
	fi

	echo "Pre-initialising structures.."
	
	init_struct

	if [[ ! -d $INSTANCE_ROOT ]] || [[ ! -d $INSTANCE_HOME ]]; then 
		echo "Directory creation failed." 
		exit 1
	fi

	echo "Initialising chroot.."

	init_chroot

	echo "Cleaning up.."

	cleanup

	echo "Finalising chroot.."

	finalise

	echo "Process complete! Use pacshrap to configure $SANDBOX."
}

parse_args () {
	ArGS=()
	for var in "$@"; do
		case $var in 
			--dep=*)
				DEPEND=$(echo $var | cut -c 7-)
				;;	
			--is-dep)
				SWITCH=d$SWITCH
				;;
			--is-root)
				SWITCH=r$SWITCH
				;;
			-C*)
				SWITCH=$(echo $var | cut -c 3-)$SWITCH
				;;
			-*)
				SWITCH=$(echo $var | cut -c 2-)$SWITCH
				;;
			*)
				SANDBOX=$var
				;;
			esac
	done
}

init_vars () {
	PACMAN_CONFIG=pacman.install.conf	
	PARAMS="$SANDBOX --root --exec"	
	INSTANCE_ROOT=$SANDBOX_BASE/fs/root/$SANDBOX
	INSTANCE_HOME=$SANDBOX_BASE/fs/home/$SANDBOX
	INSTANCE_DEP_LIST=$SANDBOX_BASE/etc/deps/$SANDBOX

	if [[ $SWITCH == *d* ]]; then
		ISDEP=1
	fi
	if [[ $SWITCH == *r* ]]; then
		ISROOTDEP=1
		PACMAN_CONFIG=pacman.conf
	fi

	BASE_ROOT=$SANDBOX_BASE/fs/root/$DEPEND
	if [[ ! $DEPEND ]] && [[ ! $ISROOTDEP ]]; then
		echo "Root dependency not specified."
		exit 1
	fi	
}


init_struct () {
	mkdir -p $INSTANCE_ROOT $INSTANCE_HOME \
		$INSTANCE_ROOT/etc \
		$INSTANCE_ROOT/var/lib/pacman \
		$INSTANCE_ROOT/etc/pacman.d/ \
		$INSTANCE_ROOT/etc/fonts/conf.d

	cp $SANDBOX_BASE/etc/pacman.conf $INSTANCE_ROOT/etc/pacman.conf
	cp $SANDBOX_BASE/etc/pacman.conf $SANDBOX_BASE/etc/pacman.d/pacman.$SANDBOX.conf
	cp $SANDBOX_BASE/etc/pacman.install.conf $INSTANCE_ROOT/etc/pacman.install.conf

	cp /etc/pacman.d/mirrorlist $INSTANCE_ROOT/etc/pacman.d/mirrorlist
	echo "en_CA.UTF-8 UTF-8" > $INSTANCE_ROOT/etc/locale.gen
	echo "LANG=en_CA.UTF-8" > $INSTANCE_ROOT/etc/locale.conf
	echo "user:x:1000:1000::/home/user:/bin/bash" >> $INSTANCE_ROOT/etc/passwd
	echo "$MACHINE_ID" > $INSTANCE_ROOT/etc/machine-id
	echo 'PS1="'$SANDBOX'> "' > $INSTANCE_HOME/.bashrc

	if [[ ! $ISROOTDEP ]]; then
		if [[ -f $SANDBOX_BASE/etc/deps/$DEPEND ]]; then
			echo "$(cat $SANDBOX_BASE/etc/deps/$DEPEND 2>/dev/null)" > $INSTANCE_DEP_LIST
			echo "$DEPEND" >> $INSTANCE_DEP_LIST
		else
			echo "$DEPEND" > $INSTANCE_DEP_LIST
		fi
	else
		touch $INSTANCE_ROOT/.root		
	fi
		
	if [[ $ISDEP ]]; then
		cp $SANDBOX_BASE/etc/pacman.tpl.conf $SANDBOX_BASE/etc/pacman.d/tpl/pacman.$SANDBOX.conf
		mkdir -p $SANDBOX_BASE/etc/db/$SANDBOX
		touch $INSTANCE_ROOT/.dep
	fi
	
}

init_chroot () {	
	fakechroot fakeroot pacman -Syu \
   	--root $INSTANCE_ROOT \
    	--dbpath $INSTANCE_ROOT/var/lib/pacman \
    	--config $INSTANCE_ROOT/etc/$PACMAN_CONFIG \
	--cache /var/lib/cache/pacman/pkg \
    	base lib32-glibc --noconfirm 2>/dev/null
	sbupdate -fbns
}

finalise () {
	$EXEC_SCRIPT $PARAMS pacman-key --init
	$EXEC_SCRIPT $PARAMS pacman-key --populate
	$EXEC_SCRIPT $PARAMS locale-gen
	$EXEC_SCRIPT $PARAMS update-ca-trust
	if [[ ! $ISROOTDEP ]]; then
		if [[ $DEPEND ]]; then		
			local deps=$(cat $INSTANCE_DEP_LIST 2>/dev/null)
			local dbsyncpkgs=

			for dep in $deps; do		
				dbsyncpkgs=$dbsyncpkgs$($EXEC_SCRIPT $dep --root --exec pacman -Qqe | sed -z -E "s/\<base\>|\<lib32-glibc\>//g")
			done
			if [[ $dbsyncpkgs ]]; then
				$EXEC_SCRIPT $PARAMS pacman -Su --dbonly --noconfirm $dbsyncpkgs 2>/dev/null
			fi
		fi
		sbupdate -gb $SANDBOX
	fi
}

cleanup () {
	rm -v -r \
	$INSTANCE_ROOT/boot \
	$INSTANCE_ROOT/mnt \
	$INSTANCE_ROOT/root \
	$INSTANCE_ROOT/srv \
	$INSTANCE_ROOT/sys \
	$INSTANCE_ROOT/opt \
	$INSTANCE_ROOT/run \
	$INSTANCE_ROOT/dev \
	$INSTANCE_ROOT/etc/pacman.install.conf
}

main $@