#!/usr/bin/bash
#
# Manage memtest86+ install location and bootloader config.
# Currently only manages GRUB with BLS support enabled.
#

# Sanity Checks
if ! [[ $KERNEL_INSTALL_MACHINE_ID ]]; then
    exit 0
fi
if ! [[ $KERNEL_INSTALL_BOOT_ROOT ]]; then
    exit 0
fi

# Setup variables
[[ -f /etc/default/grub ]] && . /etc/default/grub
[[ -f /etc/os-release ]] && . /etc/os-release

COMMAND="$1"
MEMTEST_VERSION="$2"
BOOT_DIR_ABS="$3"
MEMTEST_IMAGE="$4"

MEMTEST_DIR="${MEMTEST_IMAGE%/*}"
BOOT_ROOT="${KERNEL_INSTALL_BOOT_ROOT}"
MACHINE_ID="${KERNEL_INSTALL_MACHINE_ID}"
BLS_DIR="${BOOT_ROOT}/loader/entries"
# Fail back to /boot default if BLS_DIR
# doesn't exist already, matching 20-grub.install
if [[ ! -d "${BLS_DIR}" ]]; then
    BOOT_ROOT="/boot"
    BLS_DIR="/boot/loader/entries"
fi
BLS_ENTRY="${BLS_DIR}/${MACHINE_ID}-0-memtest86+.conf"

# Setup functions
mkbls_grub() {
    local memtestver=$1 && shift
    local memtestimg=$1 && shift

    cat <<EOF
title Memory test (${memtestimg})
version 0-${memtestver}-memtest86+
linux /${memtestimg}
grub_users \$grub_users
grub_arg --unrestricted
grub_class memtest
EOF
}

# If ${BOOT_DIR_ABS} exists, non-grub boot loader is active.
[[ -d "${BOOT_DIR_ABS}" ]] && exit 0

case "$COMMAND" in
    add)
	# Install into BOOT_ROOT, if not already there
        if [[ "${MEMTEST_DIR}" != "${BOOT_ROOT}" ]]; then
            for i in \
                "$MEMTEST_IMAGE"
            do
                [[ -e "$i" ]] || continue
                rm -f "${BOOT_ROOT}/${i##*/}"
                cp -aT "$i" "${BOOT_ROOT}/${i##*/}"
                command -v restorecon &>/dev/null && \
                    restorecon -R "${BOOT_ROOT}/${i##*/}"
            done
        fi

	# Generate GRUB BLS, if enabled
        if [[ "x${GRUB_ENABLE_BLSCFG}" = "xtrue" ]]; then
            [[ -d "$BLS_DIR" ]] || mkdir -m 0700 -p "$BLS_DIR"
            mkbls_grub "${MEMTEST_VERSION}" "${MEMTEST_IMAGE##*/}" > "${BLS_ENTRY}"
            command -v restorecon &>/dev/null && restorecon -R "${BLS_ENTRY}"

            MEMTEST_LOC="$(grep '^linux[ \t]' "${BLS_ENTRY}" | sed -e 's,^linux[ \t]*,,')"
            if [[ "$(grub2-probe --device $(grub2-probe --target=device /) --target=fs)" == "btrfs" &&
		      "${SUSE_BTRFS_SNAPSHOT_BOOTING}" == "true" ]]; then
                MEMTEST_RELPATH="$(grub2-mkrelpath -r ${BOOT_ROOT}${MEMTEST_LOC})"
            else
                MEMTEST_RELPATH="$(grub2-mkrelpath ${BOOT_ROOT}${MEMTEST_LOC})"
            fi

            BOOTPREFIX="$(dirname ${MEMTEST_RELPATH})"

            if [[ "${MEMTEST_LOC}" != "${MEMTEST_RELPATH}" ]]; then
                sed -i -e "s,^linux.*,linux ${BOOTPREFIX}${MEMTEST_LOC},g" "${BLS_ENTRY}"
            fi

            exit 77
        fi
        ;;
    remove)
        # Find MEMTEST_IMAGE location in BLS_ENTRY, delete both MEMTEST_IMAGE and BLS_ENTRY
        if [[ "x${GRUB_ENABLE_BLSCFG}" = "xtrue" ]]; then
	    if [[ -f "${BLS_ENTRY}" ]]; then
	            MEMTEST_IMAGE="$(grep '^linux[ \t]' "${BLS_ENTRY}" | sed -e 's,^linux[ \t]*,,')"
	            if [[ -f "${BOOT_ROOT}${MEMTEST_IMAGE}" ]]; then
	                    rm -f "${BOOT_ROOT}${MEMTEST_IMAGE}"
                    fi
                    rm -f "${BLS_ENTRY}"
            fi

            exit 77
        fi
        ;;
    *)
        ;;
esac