diskimage-builder/elements/ramdisk/post-install.d/99-build-ramdisk

#!/bin/bash

set -eux
set -o pipefail

_LIB="/tmp/ramdisk-build"

source $_LIB/common-defaults
source $_LIB/img-defaults
source $_LIB/ramdisk-defaults

source $_LIB/common-functions
source $_LIB/img-functions
source $_LIB/ramdisk-functions

KERNEL_VERSION=${DIB_KERNEL_VERSION:-$(find_kernel_version)}
MODULE_DIR=$MODULE_ROOT/lib/modules/$KERNEL_VERSION
FIRMWARE_DIR=$MODULE_ROOT/lib/firmware
LIB_UDEV=$LIB_UDEV_ROOT/lib/udev
INIT="$_LIB/scripts/init"
FUNCTIONS_D="$_LIB/scripts/d"
BUSYBOX=${BUSYBOX:-$(which busybox)}
# NOTE(bnemec): IMAGE_ELEMENT is normally set in disk-image-create, but we're
# not using that to build the image here.
IMAGE_ELEMENT=

mk_build_dir
mkdir -p $TMP_BUILD_DIR/mnt
export TMP_HOOKS_PATH=/tmp
export TMP_MOUNT_PATH=$TMP_BUILD_DIR/mnt

echo "building ramdisk in $TMP_MOUNT_PATH"

create_ramdisk_base
populate_lib
populate_busybox
populate_init
populate_udev
SCRIPT_HOME=/tmp/in_target.d/bin TMP_HOOKS_PATH=/tmp/in_target.d run_d ramdisk-install
finalise_image
save_image /tmp/ramdisk
# In the past save_image did this for us. If EXIT handler is not
# reset ramdisk image builds fail.
trap EXIT
cp /boot/vmlinu[zx]-${KERNEL_VERSION} /tmp/kernel
chmod o+r /tmp/kernel