appdir-qemu.sh

#!/bin/bash

# Copyright 2024 SUSE LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
# From https://github.com/rancher-sandbox/lima-and-qemu/blob/d874fe62584dcfa7e5fdd45f5225853a0240bd26/bin/appdir-lima-and-qemu.sh

# This is a helper script to build an appDir structure to include qemu as part
# of an AppImage binary.  The binaries build should happen in the oldest
# available Ubuntu LTS.

function error {
  >&2 echo "$@"
  exit 1
}

function keepListedFiles {
  local dir=$1
  local list=$2

  [ -d "${dir}" ] || error "${dir} is not a directory"

  for it in "${dir}"/*; do
    it=${it#"$dir"/}
    if [[ "${list}" =~ \ ${it}\  ]]; then
      continue
    fi
    [ -n "${it}" ] && rm -rf "${dir:?}/${it}"
  done
}

set -ex

[ -n "${1}" ] || error "One argument to the built app dir is required"
[ -d "${1}" ] || error "Directory ${1} doesn't exist"

appDir=$1
dist="qemu-linux-x86_64"

# Inspired on linuxdeployqt https://github.com/probonopd/linuxdeployqt/blob/master/tools/linuxdeployqt/excludelist.h
# Linuxdeployqt is a tool created by probonopd, the AppImage creator
excludeLibs=" libz.so.1 "
excludeLibs+="libgio-2.0.so.0 "
excludeLibs+="libgobject-2.0.so.0 "
excludeLibs+="libglib-2.0.so.0 "
excludeLibs+="libutil.so.1 "
excludeLibs+="libm.so.6 "
excludeLibs+="libgcc_s.so.1 "
excludeLibs+="libpthread.so.0 "
excludeLibs+="libc.so.6 "
excludeLibs+="libresolv.so.2 "
excludeLibs+="libdl.so.2 "
excludeLibs+="librt.so.1 "
excludeLibs+="libuuid.so.1 "
excludeLibs+="libdl.so.2 "
excludeLibs+="libgmodule-2.0.so.0 "

firmwareOfInterest=" bios-256k.bin edk2-x86_64-code.fd efi-virtio.rom kvmvapic.bin vgabios-virtio.bin "
executablesOfInterest=" qemu-system-x86_64 qemu-img "

mkdir -p "${appDir}/lib"

linkedLibs=$(ldd "${appDir}/bin/qemu-system-x86_64" | grep " => /" | cut -d" " -f3)$'\n'
linkedLibs+=$(ldd "${appDir}/bin/qemu-img" | grep " => /" | cut -d" " -f3)$'\n'
for lib in $(echo "${linkedLibs}" | sort | uniq ); do
  if [[ "${excludeLibs}" =~ \ $(basename ${lib})\  ]]; then
    continue
  fi
  cp "${lib}" "${appDir}/lib"
done

# strip docs
rm -rf "${appDir:?}/share/doc"

# remove qemu icons, includes, etc.
# We could fine tune the firmaware files
rm -rf "${appDir:?}/include"
rm -rf "${appDir:?}/libexec"
rm -rf "${appDir:?}/var"
rm -rf "${appDir:?}/share/applications"
rm -rf "${appDir:?}/share/icons"

# keep only relevant firmware
keepListedFiles "${appDir}/share/qemu" "${firmwareOfInterest}"

# keep only relevant executables
keepListedFiles "${appDir}/bin" "${executablesOfInterest}"

tar caf "${dist}.tar.gz" -C "${appDir}" .