Support engine override, support overriding some env, and improve macOS compatibility

With the latest Docker on Homebrew, build no longer works. It seems an engine
override is a nice addition, in case you prefer to not select docker as the
default choice.

Additionally, to allow forks to be more maintainable, allow the docker tag,
repository, ZBM, and EFI to be changed through env. These are exposed through
env since most users should not customize these.

Use the latest released ZBM as the default.

Improve macOS compatibility by using GNU versions for du and stat.
inject (stat), and iso (du) are fixed by checking for GNU versions.

Signed-off-by: Daniel Vicory <dvicory@gmail.com>

Author: dvicory

Dockerfile

@@ -10,7 +10,6 @@
 
 # Use the official Void Linux container
 FROM ghcr.io/void-linux/void-glibc-full 
-LABEL org.opencontainers.image.source=https://github.com/midzelis/zquickinit
 
 ARG XBPS_REPOS="https://repo-fastly.voidlinux.org/current https://repo-fastly.voidlinux.org/current/nonfree"
 

zquickinit.sh

@@ -27,21 +27,35 @@ SRC_ROOT=${DIR}
 ZBM_ROOT=${SRC_ROOT}/../zfsbootmenu
 RECIPES_ROOT=${RECIPES_ROOT:-${SRC_ROOT}/recipes}
 
-RECIPE_BUILDER="ghcr.io/midzelis/zquickinit"
-ZQUICKEFI_URL="https://github.com/midzelis/zquickinit/releases/latest"
-# if empty, use latest release tag
-ZBM_TAG=
+RECIPE_BUILDER="${RECIPE_BUILDER:-ghcr.io/midzelis/zquickinit}"
+ZQUICKINIT_REPO="${ZQUICKINIT_REPO:-https://github.com/midzelis/zquickinit}"
+ZQUICKEFI_URL="${ZQUICKEFI_URL:-${ZQUICKINIT_REPO}/releases/latest}"
+
+# provide default stable, latest ZBM_TAG if not specified
+ZBM_TAG="${ZBM_TAG:-v3.0.1}"
+# if empty, then unset to get latest release
+if [[ -z "$ZBM_TAG" ]]; then
+	ZBM_TAG=""
+fi
+
 # if specified, takes precedence over ZBM_TAG
-ZBM_COMMIT_HASH=db78c980f40937f3b4de8d85e7430f6553a39972
+ZBM_COMMIT_HASH="${ZBM_COMMIT_HASH:-}"
+# if ZBM_COMMIT_HASH is specified, unset ZBM_TAG
+if [[ -n "$ZBM_COMMIT_HASH" ]]; then
+	ZBM_TAG=""
+fi
+
 INPUT=/input
 OUTPUT=/output
 ADD_LOADER=
 MKINIT_VERBOSE=
 KERNEL_BOOT=
 ENGINE=
 OBJCOPY=
+DU=
 FIND=
 YG=
+STAT=
 NOASK=0
 DEBUG=0
 ENTER=0
@@ -101,10 +115,10 @@ check() {
 		fi
 	fi
 	if [[ $1 == docker || $1 == podman ]]; then
-		if command -v docker &>/dev/null; then
+		if [ -z "$ENGINE" ] && command -v docker &>/dev/null; then
 			ENGINE=docker
 			return 0
-		elif command -v podman &>/dev/null; then
+		elif [ -z "$ENGINE" ] && command -v podman &>/dev/null; then
 			ENGINE=podman
 			return 0
 		fi
@@ -142,17 +156,6 @@ check() {
 			OBJCOPY=objcopy
 		fi
 	fi
-	if ! command -v "$1" &>/dev/null; then
-		echo "$1 not found. usually part of the $2 package"
-		if [[ $1 == "gum" && -f "/etc/debian_version" ]]; then
-			echo "To install, try:"
-			echo 'sudo mkdir -p /etc/apt/keyrings'
-			echo 'curl -fsSL https://repo.charm.sh/apt/gpg.key | sudo gpg --dearmor -o /etc/apt/keyrings/charm.gpg'
-			echo 'echo "deb [signed-by=/etc/apt/keyrings/charm.gpg] https://repo.charm.sh/apt/ * *" | sudo tee /etc/apt/sources.list.d/charm.list'
-			echo 'sudo apt update && sudo apt install gum'
-		fi
-		exit 1
-	fi
 	if [[ $1 == find ]] && [[ -z "${FIND}" ]]; then
 		if command -v gfind &>/dev/null; then
 			FIND="gfind"
@@ -168,6 +171,47 @@ check() {
 			exit 1
 		fi
 	fi
+	if [[ $1 == du ]] && [[ -z "${DU}" ]]; then
+		if command -v gdu &>/dev/null; then
+			DU="gdu"
+		else
+			DU="du"
+		fi
+		if [[ ! "$(${DU} --version 2>&1 | head -n1)" == *GNU* ]]; then
+			echo "du must be GNU flavored. Update or install coreutils package. "
+			if [[ "$OSTYPE" == "darwin"* ]]; then
+				echo "On MacOS, use brew to install coreutils"
+				echo "Note: brew uses /usr/local/bin on Intel, and /opt/homebrew/bin on Apple"
+			fi
+			exit 1
+		fi
+	fi
+	if [[ $1 == stat ]] && [[ -z "${STAT}" ]]; then
+		if command -v gstat &>/dev/null; then
+			STAT="gstat"
+		else
+			STAT="stat"
+		fi
+		if [[ ! "$(${STAT} --version 2>&1 | head -n1)" == *GNU* ]]; then
+			echo "stat must be GNU flavored. Update or install coreutils package. "
+			if [[ "$OSTYPE" == "darwin"* ]]; then
+				echo "On MacOS, use brew to install coreutils"
+				echo "Note: brew uses /usr/local/bin on Intel, and /opt/homebrew/bin on Apple"
+			fi
+			exit 1
+		fi
+	fi
+	if ! command -v "$1" &>/dev/null; then
+		echo "$1 not found. usually part of the $2 package"
+		if [[ $1 == "gum" && -f "/etc/debian_version" ]]; then
+			echo "To install, try:"
+			echo 'sudo mkdir -p /etc/apt/keyrings'
+			echo 'curl -fsSL https://repo.charm.sh/apt/gpg.key | sudo gpg --dearmor -o /etc/apt/keyrings/charm.gpg'
+			echo 'echo "deb [signed-by=/etc/apt/keyrings/charm.gpg] https://repo.charm.sh/apt/ * *" | sudo tee /etc/apt/sources.list.d/charm.list'
+			echo 'sudo apt update && sudo apt install gum'
+		fi
+		exit 1
+	fi
 }
 
 # This will build the main ZquickInit Builder OCI image
@@ -197,6 +241,7 @@ builder() {
 	echo
 	cmd=("$ENGINE" build .
 		-t "$RECIPE_BUILDER"
+		--label org.opencontainers.image.source="${ZQUICKINIT_REPO}"
 		--build-arg KERNELS=linux6.6
 		--build-arg "PACKAGES=${packages[*]}"
 		--build-arg ZBM_COMMIT_HASH="${ZBM_COMMIT_HASH}"
@@ -225,6 +270,7 @@ tailscale() {
 make_zquick_initramfs() {
 	check gum gum
 	check mkinitcpio mkinitcpio
+	check stat stat
 
 	gum style --bold --border double --align center \
 		--width 50 --margin "1 2" --padding "0 2" "Welcome to ZQuickInit make initramfs"
@@ -234,13 +280,13 @@ make_zquick_initramfs() {
 		local hash
 		echo "Downloading zquickinit"
 		rm -rf "${INPUT}"
-		git clone --quiet --depth 1 https://github.com/midzelis/zquickinit.git "${INPUT}"
+		git clone --quiet --depth 1 "${ZQUICKINIT_REPO}" "${INPUT}"
 		hash=$(cat /etc/zquickinit-commit-hash || echo '')
 		if [[ -n "${hash}" ]]; then
 			(cd "${INPUT}" && git fetch --depth 1 origin "$hash" && git checkout FETCH_HEAD)
 		fi
 	fi
-	[[ -x /etc/zquickinit-commit-hash ]] && (cd "${INPUT}" && git config --global --add safe.directory "${INPUT}" && /etc/zquickinit-commit-hash && git rev-parse HEAD >/etc/zquickinit-commit-hash && echo "ZQuickInit (https://github.com/midzelis/zquickinit) commit hash: $(git rev-parse --short HEAD) ($(git rev-parse HEAD))")
+	[[ -x /etc/zquickinit-commit-hash ]] && (cd "${INPUT}" && git config --global --add safe.directory "${INPUT}" && /etc/zquickinit-commit-hash && git rev-parse HEAD >/etc/zquickinit-commit-hash && echo "ZQuickInit (${ZQUICKINIT_REPO}) commit hash: $(git rev-parse --short HEAD) ($(git rev-parse HEAD))")
 
 	if [[ ! -f "${ZBM}/bin/generate-zbm" ]]; then
 		echo "Downloading latest zfsbootmenu"
@@ -576,9 +622,9 @@ make_zquick_initramfs() {
 	)
 	chmod o+rw -R "${OUTPUT}"/*
 	chmod g+rw -R "${OUTPUT}"/*
-	env LC_ALL=en_US.UTF-8 printf "Kernel size: \t\t%'.0f bytes\n" "$(stat -c '%s' "${OUTPUT}/zquickinit-$build_time.vmlinuz-$kernel")"
-	env LC_ALL=en_US.UTF-8 printf "initramfs size: \t%'.0f bytes\n" "$(stat -c '%s' "$output_img")"
-	env LC_ALL=en_US.UTF-8 printf "EFI size: \t\t%'.0f bytes\n" "$(stat -c '%s' "$output_uki")"
+	env LC_ALL=en_US.UTF-8 printf "Kernel size: \t\t%'.0f bytes\n" "$(${STAT} -c '%s' "${OUTPUT}/zquickinit-$build_time.vmlinuz-$kernel")"
+	env LC_ALL=en_US.UTF-8 printf "initramfs size: \t%'.0f bytes\n" "$(${STAT} -c '%s' "$output_img")"
+	env LC_ALL=en_US.UTF-8 printf "EFI size: \t\t%'.0f bytes\n" "$(${STAT} -c '%s' "$output_uki")"
 	find "${OUTPUT}" -name 'zquickinit*.img' | sort -r | tail -n +4 | xargs -r rm
 	find "${OUTPUT}" -name 'zquickinit*.efi' | sort -r | tail -n +4 | xargs -r rm
 	find "${OUTPUT}" -name 'zquickinit*.vmlinuz-*' | sort -r | tail -n +4 | xargs -r rm
@@ -631,7 +677,7 @@ getefi() {
 		echo "No image found, finding latest release..."
 		local version='' download=''
 		version=$(curl --silent -qI "${ZQUICKEFI_URL}" | awk -F '/' '/^location/ {print  substr($NF, 1, length($NF)-1)}')
-		download="https://github.com/midzelis/zquickinit/releases/download/$version/zquickinit.efi"
+		download="${ZQUICKINIT_REPO}/releases/download/$version/zquickinit.efi"
 		source="${tmp}/zquickinit-${version}.efi"
 		echo "Downloading from ${download} to ${source}..."
 		curl -o "$source" --progress-bar -L "${download}"
@@ -736,6 +782,7 @@ inject() {
 		check bsdtar "libarchive-tools"
 		check objcopy binutils
 		check truncate coreutils
+		check stat coreutils
 		check find findutils
 
 		echo "Secrets were injected, appending '_injected' to name"
@@ -753,7 +800,7 @@ inject() {
 		# To append an additional initrd segment, the new archive must aligned to a
 		# 4-byte boundary: https://unix.stackexchange.com/a/737219
 
-		initrd_size=$(stat -c '%s' "${initrd}")
+		initrd_size=$(${STAT} -c '%s' "${initrd}")
 		initrd_size=$(((initrd_size + 3) / 4 * 4))
 		truncate -s "${initrd_size}" "${initrd}"
 
@@ -829,6 +876,7 @@ iso() {
 	check xorriso xorriso
 	check truncate coreutils
 	check find findutils
+	check du coreutils
 
 	local target=${1:-zquickinit.iso}
 	local source=${2:-}
@@ -844,7 +892,7 @@ iso() {
 	local isoroot="${tmp}/iso"
 	mkdir -p "${isoroot}"
 	local size
-	read -ra size <<<"$(du --apparent-size --block-size=1M "$source")"
+	read -ra size <<<"$(${DU} --apparent-size --block-size=1M "$source")"
 	local padded=$((size[0] + 12))
 	local part_img="${tmp}/efs_partition.img"
 	rm -rf "${part_img}"
@@ -878,6 +926,7 @@ playground() {
 	check truncate coreutils
 	check qemu-system-x86_64 qemu
 	check find findutils
+	check nproc coreutils
 
 	# shellcheck disable=SC2155
 	local tmp=$(tmpdir)
@@ -1101,6 +1150,12 @@ if [[ $(type -t "$command") == function ]]; then
 				shift
 			fi
 			;;
+		--engine)
+			if [[ -n ${2:-} ]]; then
+				ENGINE=$2
+				shift
+			fi
+			;;
 		--no-container)
 			NOCONTAINER=1
 			;;
@@ -1188,6 +1243,7 @@ else
 	echo "    --no-container Do not use containers to build initramfs"
 	echo "    --release     Do not add QEMU debug, or any secrets"
 	echo "    --secrets <dir> Use this folder for secrets."
+	echo "    --engine  <docker|podman> Override automatic detection to use specific engine."
 	echo "    -d,--debug    Advanced: Turn on tracing"
 	echo "    -e,--enter    Advanced: Do not build an image. Execute bash and"
 	echo "                  enter the builder image."