git-apply-debian-patches

#!/bin/bash -eu
# Author:
#   Edward Hope-Morley <opentastic@gmail.com>
#
# Description:
#   Fetches package source and applies all debian/patches to current git
#   working tree (ideally a clean branch created from associated build tag ).
#
#   Each patch will be committed once applied successfully.
#
PATH_NOTE="this script must be run within the git repo you want to apply patches to."
ARG_SOURCE_NAME=
ARG_UBUNTU_VER=

usage ()
{
    echo "USAGE: `basename $0` <package> -h -u -t <tag>"
}

if ! [ -d .git ]; then
    echo "ERROR: $PATH_NOTE"
    exit 1
fi

(($#)) || { usage; exit 1; }
while (($#)); do
    case $1 in
        -u)
            sudo apt-get update
            ;;
        -h)
            usage
            exit 0
            ;;
        --version)
            ARG_UBUNTU_VER="$2"
            shift
            ;;
        -v|--verbose)
            set -x
            ;;
        *)
            ARG_SOURCE_NAME="$1"  # e.g. nova
            ;;
    esac
    shift
done

if [ -z $ARG_UBUNTU_VER ]; then
    echo "Fetching versions..."
    ARG_UBUNTU_VER="`apt-cache policy $ARG_SOURCE_NAME| grep " Candidate: "| awk '{print $2}'`"
    if [ -z "$ARG_UBUNTU_VER" ]; then
        pkg="`apt-cache showsrc $ARG_SOURCE_NAME| grep -A1 Package-List:| tail -n 1| awk '{print $1}'`"
        ARG_UBUNTU_VER="`apt-cache policy $pkg| grep " Candidate: "| awk '{print $2}'`"
    fi
else
    echo "Using supplied ubuntu package version '$ARG_UBUNTU_VER'"
fi
git_commit_header="Import from ubuntu $ARG_SOURCE_NAME package $ARG_UBUNTU_VER"
deb_ver=`echo $ARG_UBUNTU_VER| sed 's/[1:]*\(.*\)-.*/\1/'`
echo -e "Current debian version of $ARG_SOURCE_NAME is $deb_ver"

# Always use a fresh branch
branch_name="sru-sync-${deb_ver}-`date +%s`"
if `git branch -a| grep -q $branch_name`; then
    echo "ERROR: a branch named '$branch_name' already exists"
fi
echo "Creating new git branch '$branch_name' from tag '$deb_ver'"
git checkout -b $branch_name $deb_ver

tmpdir=`mktemp -d`
echo -e "\nUsing tmpdir='$tmpdir' to download apt-source"
(
cd $tmpdir
apt-get source $ARG_SOURCE_NAME=$ARG_UBUNTU_VER
)

patches_path=$tmpdir/${ARG_SOURCE_NAME}-${deb_ver}/debian/patches
series_path=$patches_path/series

echo -e "\nApplying patches from $patches_path to current working tree"
while read -r patch; do
    if [ '#' = "${patch:0:1}" ]; then
        continue
    fi
    echo "Applying $patch"
    git apply < $patches_path/$patch
    git commit -a -m "$git_commit_header
  - d/p/$patch"
done < $series_path

# Cleanup
rm -rf $tmpdir

echo -e "\nDone."