build-sysroot

#!/bin/sh -eu

. $BULB_SH_UTILS

usage() {
	echo "
Usage: ${0##*/} [options] executable...
options:
        -i In system's root directory
        -o Out system's root directory
        -m Install missing libraries
        -h Print this help and exit
"
}

list_append() {
	l_list=${1:-}
	shift
	[ -z "$l_list" ] || printf '%s\n' "$l_list"
	[ $# -eq 0 ] || printf '%s\n' "$@"
}

check_arch() {
	l_bin_path=${1:-}
	l_desired_arch=${2:-}
	[ -n "$l_bin_path" ] || croak The binary path parameter is missing

	l_file_arch=$(file -b "$l_bin_path" |sed 's/[^,]*, \([^,]*\).*/\1/')
	l_arch=
	case $l_file_arch in
	ARM)
		l_arch=armhf
		;;
	'ARM aarch64')
		l_arch=arm64
		;;
	x86-64)
		l_arch=amd64
		;;
	*)
		croak $l_file_arch is not a supported architecture
		;;
	esac
	[ -z "$l_desired_arch" ] || [ "$l_arch" = "$l_desired_arch" ] || croak "The binary $l_bin_path is of architecture $l_arch which is not desired (desire=$l_desired_arch)"
	echo $l_arch
}

find_pkgs() {
	l_arch=${1:-}
	[ -n "$l_arch" ] || croak The architecture parameter is missing
	shift
	dpkg --add-architecture $l_arch
	apt-file -a $l_arch update >/dev/null
	for l_file in "$@"; do
		# Find and choose the package with the shortest name that contains the needed library
		apt-file -l -a $l_arch find "$l_file" |{
			l_pkg=
			while read l_line; do
				l_pkg=${l_pkg:=$l_line}
				[ ${#l_line} -lt ${#l_pkg} ] && l_pkg=$l_line
			done
			if [ -n "$l_pkg" ]; then
				printf '%s ' $l_pkg
			else
				bark no package containing $l_file
			fi
		}
	done
}

get_missing_libs() {
	local l_bin_path=${1:-}
	local l_root_dir=${2:+-r$2}
	[ -n "$l_bin_path" ] || croak The binary path parameter is missing
	ld-trace "$l_root_dir" "$l_bin_path" |{
		while read l_line; do
			lib_path=${l_line#*=> }
			lib=${l_line% =>*}
			[ "$lib_path" != 'not found' ] || printf '%s\n' "$lib"
		done
	}
}

get_lib_paths() {
	local l_bin_path=${1:-}
	local l_root_dir=${2:+-r$2}
	[ -n "$l_bin_path" ] || croak The binary path parameter is missing
	ld-trace "$l_root_dir" "$l_bin_path" |{
		while read l_line; do
			lib_path=${l_line#*=> }
			lib=${l_line% =>*}
			[ "$lib_path" = 'not found' ] || [ "${lib_path%% \'*}" = 'removed' ] || [ "$lib_path" = "$lib" ] || {
				lib_path=${lib_path% (*}
				case $lib_path in
				/*)
					lib_path=".$lib_path"
					;;
				*)
					;;
				esac
				printf '%s\n' "$lib_path"
			}
		done
	}
}

install_missing() {
	l_root_dir=${1:-}
	l_arch=${2:-}
	[ -n "$l_root_dir" ] || croak The root directory parameter is missing
	[ -n "$l_arch" ] || croak The architecture parameter is missing
	shift 2

	l_missing_libs=
	for l_bin_path in "$@"; do
		l_missing_libs="$(get_missing_libs "$l_bin_path" "$l_root_dir")
$l_missing_libs"
	done

	[ -n "$l_missing_libs" ] && install_libs_pkgs "$l_root_dir" $l_arch $l_missing_libs
}

install_libs_pkgs() {
	l_root_dir=${1:-}
	l_arch=${2:-}
	[ -n "$l_root_dir" ] || croak The root directory parameter is missing
	[ -n "$l_arch" ] || croak The architecture parameter is missing
	shift 2
	local l_pkgs=$(find_pkgs $l_arch $*)
	[ -z "$l_pkgs" ] || install-pkgs -a $l_arch -r "$l_root_dir" $l_pkgs >/dev/null
}

in_sysroot=
out_sysroot=
install_missing=
while getopts 'i:o:mh' opt; do
	case $opt in
	i)
		in_sysroot=$(get_absolut_path $OPTARG)
		;;
	o)
		out_sysroot=$(get_absolut_path $OPTARG)
		;;
	m)
		install_missing=y
		;;
	h)
		usage
		exit
		;;
	*)
		usage
		exit 1
		;;
	esac
done

shift $((OPTIND - 1))

[ $# -gt 0 ] || {
	usage
	exit
}

tmp_in_sysroot=
[ -n "$in_sysroot" ] || {
	tmp_in_sysroot=$(mktemp -d)
	in_sysroot=$tmp_in_sysroot
}

out_sysroot=${out_sysroot:-$(mktemp -d)}

[ -d "$out_sysroot" ] || install -d $out_sysroot 2>/dev/null || croak $out_sysroot is not a directory
echo out_sysroot: $out_sysroot

IFS="$(printf '\n\t')"

bin_paths=
arch=
rtld=
for bin in "$@"; do
	bin_path=$(get_absolut_path $bin)
	arch=$(check_arch $bin_path $arch)
	[ -n "$rtld" ] || rtld=$(file -b "$bin_path" |sed 's/.*, interpreter \([^,]*\).*/\1/')
	bin_paths=$(list_append "$bin_paths" "$bin_path")
done

[ -z "$install_missing" ] || install_missing "$in_sysroot" $arch $bin_paths

lib_paths=
for bin_path in $bin_paths; do
	bin_lib_paths=$(get_lib_paths "$bin_path" "$in_sysroot")
	lib_paths=$(list_append "$lib_paths" "$bin_lib_paths")
done

lib_paths=$(echo "$lib_paths" |sort -u)


[ -z "$lib_paths" ] || {
	cd "$in_sysroot"
	for lib_path in $lib_paths; do
		cp --parents "$lib_path" "$out_sysroot"
	done
}

cp --parents $rtld "$out_sysroot"

install -D -t "$out_sysroot"/usr/bin/ $bin_paths

[ -z "$tmp_in_sysroot" ] || rm -rf $tmp_in_sysroot
echo $out_sysroot