feat(build): Add build-rootfs.sh to build for foreign arch

This script can be used to build and run package without CI

Output will be:

./build/*-*${arch}.deb

It has been tested on debian-12.

This change has been adapted from version I made in other projects (see related link).

Also, I have adjusted the licence to comply current OSS policy,
as it is not embedded code, it can be relaxed from MSLA to ZLIB.

Origin: #11
Relate-to: SiliconLabs/zipgateway#4
Relate-to: SiliconLabsSoftware/z-wave-protocol-controller#5
Signed-off-by: Philippe Coval <philippe.coval@silabs.com>

Author: rzr

extra/build/build-rootfs.sh

@@ -0,0 +1,164 @@
+#! /usr/bin/env bash
+# -*- mode: Bash; tab-width: 2; indent-tabs-mode: nil; coding: utf-8 -*-
+# vim:shiftwidth=4:softtabstop=4:tabstop=4:
+# SPDX-License-Identifier: Zlib
+# SPDX-License-URL: https://spdx.org/licenses/Zlib
+# SPDX-FileCopyrightText: Silicon Laboratories Inc. https://www.silabs.com
+
+set -e
+set -x
+
+cat<<EOF
+Usage:
+
+ARCH=arm64 ./scripts/build-rootfs.sh
+EOF
+
+project="z-wave-nvm-migration-tool"
+debian_suite="${debian_suite:=bookworm}"
+debian_arch=$(dpkg --print-architecture)
+
+# Can be overloaded from env eg: ARCH=arm64"
+target_debian_arch=${ARCH:="${debian_arch}"}
+
+debian_mirror_url="http://deb.debian.org/debian"
+sudo="sudo"
+machine="${project}-${debian_suite}-${target_debian_arch}-rootfs"
+rootfs_dir="/var/tmp/var/lib/machines/${machine}"
+MAKE="/usr/bin/make"
+CURDIR="$PWD"
+chroot="systemd-nspawn"
+packages="debootstrap \
+  debian-archive-keyring \
+  systemd-container \
+  time \
+"
+
+# Guess values to be adjusted
+CMAKE_SYSTEM_PROCESSOR="$ARCH"
+qemu_arch="${ARCH}"
+qemu_system="qemu-system-${qemu_arch}"
+qemu_package="${qemu_system}"       
+
+case $target_debian_arch in
+    amd64)
+        qemu_system="qemu-system-${CMAKE_SYSTEM_PROCESSOR}"
+        export CMAKE_SYSTEM_PROCESSOR="x86_64"
+        qemu_package="qemu-system-x86"
+        ;;
+
+    arm64)
+        qemu_arch="aarch64"
+        qemu_system="qemu-system-${qemu_arch}"
+        export CMAKE_SYSTEM_PROCESSOR="${qemu_arch}"
+        qemu_package="qemu-system-arm"
+        ;;
+
+    armhf)
+        debian_arch="armhf"
+        qemu_arch="arm"
+        qemu_system="qemu-system-${qemu_arch}"
+        export CMAKE_SYSTEM_PROCESSOR="armv7l"
+        qemu_package="qemu-system-arm"
+
+        # Workaround: https://github.com/armbian/build/issues/5330
+        binfmt_file="/var/lib/binfmts/qemu-${qemu_arch}"
+        [ -e "$binfmt_file" ] || cat<<EOF \
+                | { sudo mkdir -p /var/lib/binfmts && sudo tee "$binfmt_file" ; }
+package qemu-user-static
+interpreter /usr/libexec/qemu-binfmt/arm-binfmt-P
+magic \x7f\x45\x4c\x46\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x28\x00
+offset 0
+mask \xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff
+credentials yes
+fix_binary no
+preserve yes
+EOF
+        ;;
+    i386)
+        MAKE="linux32 ${MAKE}"
+        ;;
+    *)
+        echo "warning: Not supported yet"
+        ;;
+esac
+qemu_file="/usr/bin/${qemu_system}"
+binfmt_file="/var/lib/binfmts/qemu-${qemu_arch}"
+
+${sudo} apt-get update
+${sudo} apt install -y ${packages}
+
+if [ "${debian_target_arch}" != "${debian_arch}" ] ; then
+    echo "log: ${ARCH}: Support foreign arch: ${qemu_arch}"
+    ${sudo} apt-get update
+    packages="binfmt-support qemu-user-static ${qemu_package}"
+    ${sudo} apt install -y ${packages}
+
+    if [ -e "${qemu_file}" ]; then
+        ${sudo} update-binfmts --enable "qemu-${qemu_arch}" \
+            || find /usr/libexec/qemu-binfmt/
+    fi
+fi
+
+if [ ! -d "${rootfs_dir}" ] ; then
+    ${sudo} mkdir -pv "${rootfs_dir}"
+    time ${sudo} debootstrap \
+         --arch="${target_debian_arch}" \
+	       "${debian_suite}" "${rootfs_dir}" "${debian_mirror_url}"
+    ${sudo} chmod -v u+rX "${rootfs_dir}"
+fi
+
+### Environement to pass
+
+env_vars_options=""
+for i in $env_vars; do
+    env_vars_options="$env_vars_options --setenv=$i"
+done
+
+### Workarounds/Optimizations
+
+case ${chroot} in
+    "systemd-nspawn")
+        rootfs_shell="${sudo} systemd-nspawn \
+ --directory="${rootfs_dir}" \
+ --machine="${machine}" \
+ --bind="${CURDIR}:${CURDIR}" \
+ $env_vars_options
+"
+        if [ -e "${qemu_file}" ] ; then
+            rootfs_shell="$rootfs_shell --bind ${qemu_file}"
+        fi
+        ;;
+    *)
+        rootfs_shell="${sudo} chroot ${rootfs_dir}"
+        l="dev dev/pts sys proc"
+        for t in $l ; do
+            $sudo mkdir -p "${rootfs_dir}/$t"
+            $sudo mount --bind "/$t" "${rootfs_dir}/$t"
+        done
+    ;;
+esac
+
+${rootfs_shell} \
+    apt-get install -y -- make sudo util-linux git
+
+# echo "log: To prevent 'fatal: detected dubious ownership in repository'"
+${rootfs_shell} \
+    git config --global --add safe.directory "${CURDIR}"
+
+args="help setup default"
+[ "$1" = "" ] || args="$@"
+
+${rootfs_shell}	\
+    ${MAKE} \
+    --directory="${CURDIR}" \
+    --file="${CURDIR}/helper.mk" \
+    USER="${USER}" \
+    ${env_vars} \
+    -- \
+    ${args} \
+    target_debian_arch="${target_debian_arch}" \
+    CMAKE_SYSTEM_PROCESSOR="${CMAKE_SYSTEM_PROCESSOR}" \
+    # EoL
+
+echo "sudo du -hs -- '/var/tmp/var/lib/machines/${machine}' # can be removed now"