aufs-genpatch.sh

#!/bin/sh

linux_base=$1
out_dir=$2

if [ -z "$1" ]
then linux_base="4.5"
fi

if [ -z "$2" ]
then out_dir=$(readlink -f $0 | xargs -r0 dirname)
fi

###

D=/dev/null

GH_user="sfjro"
GH_repo="aufs4-standalone"
GH_branch="aufs${linux_base}"
GH_tarball="https://github.com/${GH_user}/${GH_repo}/archive/${GH_branch}.tar.gz"
GH_tarball_topdir="${GH_repo}-${GH_branch}"

aufs_reldate_src="include/uapi/linux/aufs_type.h"
aufs_reldate_re="^[[:space:]]*#define[[:space:]]+AUFS_VERSION[[:space:]]+\"(${linux_base}-([^\"]+))\"[[:space:]]*\$"
aufs_reldate_raw=""
aufs_reldate=""

aufs_tree="Documentation/ fs/ include/uapi/linux/aufs_type.h"

rename_old="aufs4-common.patch  aufs4-kbuild.patch  aufs4-base.patch  aufs4-mmap.patch  aufs4-standalone.patch  aufs4-loopback.patch    vfs-ino.patch    tmpfs-idr.patch"
rename_new="    0-common.patch      1-kbuild.patch      2-base.patch      3-mmap.patch      4-standalone.patch      5-loopback.patch  6-vfs-ino.patch  7-tmpfs-idr.patch"

###

cleanup() {
[ -n "${tmpdir_tarball}" ]  && [ -d "${tmpdir_tarball}" ]  && rm -rf "${tmpdir_tarball}"
[ -n "${tmpdir_gitrepo}" ]  && [ -d "${tmpdir_gitrepo}" ]  && rm -rf "${tmpdir_gitrepo}"

[ -n "${tmpfile_tarball}" ] && [ -f "${tmpfile_tarball}" ] && rm  -f "${tmpfile_tarball}"
}
failfast() { cleanup; exit 1; }

### fetch tarball from GitHub

tmpfile_tarball=$(mktemp)
wget -q -O "${tmpfile_tarball}" "${GH_tarball}" <${D} >${D} 2>${D} || failfast

### extract tarball

tmpdir_tarball=$(mktemp -d)
tar -x -f "${tmpfile_tarball}" -C "${tmpdir_tarball}" <${D} >${D} 2>${D} || failfast
rm -f "${tmpfile_tarball}"

### extract AuFS version info from header file and assign it to variable

tarball_dir="${tmpdir_tarball}/${GH_tarball_topdir}"

eval $(sed -nre "/${aufs_reldate_re}/{s##aufs_reldate_raw=\1\naufs_reldate=\2#;p}" < "${tarball_dir}/${aufs_reldate_src}")

[ -z "${aufs_reldate_raw}" ] && failfast

### generate patch which adds common files (according to README)

tmpdir_gitrepo=$(mktemp -d)

cd "${tmpdir_gitrepo}"
git init <${D} >${D} 2>${D}
git commit --allow-empty -m "0" <${D} >${D} 2>${D}

cd "${tarball_dir}"
tar -cf - ${aufs_tree} | tar -xf - -C "${tmpdir_gitrepo}"

cd "${tmpdir_gitrepo}"
git add . <${D} >${D} 2>${D}

common_patch="${tarball_dir}/aufs4-common.patch"
: > "${common_patch}"
echo "${GH_branch} common files patch" >> "${common_patch}"
echo >> "${common_patch}"
git diff HEAD <${D} 2>${D} >> "${common_patch}"

cd "${tarball_dir}"
rm -rf "${tmpdir_gitrepo}"

### move all files from tarball dir to destination dir

k=$(echo "${rename_old}" | xargs -n1 | wc -l)

rename_old=$(echo "${rename_old}" | sed -re "s#^ *([^ ].*[^ ]) *\$#\1#g" | tr -s " " "|")
rename_new=$(echo "${rename_new}" | sed -re "s#^ *([^ ].*[^ ]) *\$#\1#g" | tr -s " " "|")

i=0
while [ ${i} -lt ${k} ]; do
    i=$((i+1))

    old_name=$(echo "${rename_old}" | cut -d"|" -f${i})
    new_name=$(echo "${rename_new}" | cut -d"|" -f${i})
    new_name="${out_dir}/${linux_base}-${aufs_reldate}-${new_name}"

    mv "${old_name}" "${new_name}"
done

cd "${out_dir}"

cleanup