UBUNTU: [Packaging] update helper scripts

[mirror_ubuntu-kernels.git] / debian / scripts / helpers / rebase

#!/bin/bash -e
#
# This script is intended as a helper when rebasing from its master branch.
#

LOCAL_BRANCH=
RELEASE_REPO=
SOURCE_RELEASE_BRANCH=
OWN=

function out()
{
	local rc="${?}"
	trap - EXIT INT TERM HUP
	[ "${rc}" -eq 0 ] || echo "Error: Script failed"
	exit "${rc}"
}

trap out EXIT INT TERM HUP

if [ -f debian/debian.env ]; then
	# shellcheck disable=SC1091
	. debian/debian.env
fi

if [ ! -d "${DEBIAN}" ]; then
	echo You must run this script from the top directory of this repository.
	exit 1
fi

CONF="${DEBIAN}"/etc/update.conf
if [ -f "${CONF}" ]; then
	# shellcheck disable=SC1090
	. "${CONF}"
fi

usage="$0 [-r RELEASE_REPO] [ -b REMOTE_BRANCH ] [-l LOCAL_BRANCH] [-d]"$'\n\n'
usage+="-r RELEASE_REPO		Git repository to fetch the reference branch from."$'\n'
usage+="-b REMOTE_BRANCH	Remote branch to fetch from."$'\n'
usage+="-l LOCAL_BRANCH		Use LOCAL_BRANCH as the reference branch."$'\n'
usage+="-o 			Rebase against own kernel."$'\n'
usage+="-d 			Dry run (do not rebase)."

#
# command line options:
# [-r RELEASE_REPO]  - override default git repository.
# [-b REMOTE_BRANCH] - override default remote branch.
# [-l LOCAL_BRANCH]  - do not fetch from remote repo, use a local branch.

while getopts "r:b:l:od" opt; do
	case $opt in
	r ) RELEASE_REPO="$OPTARG" ;;
	b ) SOURCE_RELEASE_BRANCH="$OPTARG" ;;
	l ) LOCAL_BRANCH="$OPTARG" ;;
	d ) DRY_RUN=1 ;;
	o ) OWN=1 ;;
	\? ) echo "usage: ${usage}"; exit ;;
	esac
done
shift $((OPTIND - 1))

# For normal trees the fact that the update.conf file exists means that they are rebase
# kernels. There are some special trees which started with uc20-efi, which have that
# file because they logically depend on another source but do not have the directory
# which DEBIAN_MASTER points to.
IS_REBASE_KERNEL=true
if [ ! -f "$DEBIAN/etc/update.conf" ]; then
        IS_REBASE_KERNEL=false
elif [ "$DEBIAN_MASTER" != "" -a ! -d "$DEBIAN_MASTER" ]; then
        IS_REBASE_KERNEL=false
fi
if ! $IS_REBASE_KERNEL && [ -z "$OWN" ]; then
	echo "This is not a rebase kernel, no rebase should be needed, please report if otherwise"
	exit 0
fi

if [ "${OWN}" ] ; then
	DEBIAN_MASTER="${DEBIAN}"
fi

if [ "$DEBIAN_MASTER" = "" ]; then
	echo "DEBIAN_MASTER should be defined either in ${DEBIAN}/etc/update.conf or the environment"
	exit 1
fi

if [ -z "${LOCAL_BRANCH}" ]; then
	if [ -z "${RELEASE_REPO}" ] || [ -z "${SOURCE_RELEASE_BRANCH}" ]; then
		echo Missing update.conf or missing parameters for remote repo and branch.
		exit 1
	fi
	#
	# Fetch the upstream branch.
	#
	git fetch "${RELEASE_REPO}"
	git fetch "${RELEASE_REPO}" "${SOURCE_RELEASE_BRANCH}"
	LOCAL_BRANCH=FETCH_HEAD
fi

#
# Find the most recent tag on given upstream branch, then
# rebase against it. This avoids the case where there have been some
# commits since the last official tag.
#
MASTER_COMMIT=$(git log --pretty=one "${LOCAL_BRANCH}" "${DEBIAN_MASTER}" | \
    awk '
	/Ubuntu-/ {
		if (match($0, /UBUNTU: Ubuntu-/)) {
				print $1
				exit
                        }
                }
        '
)
#
# Find the current merge point where current branch was based.
#
BASE_COMMIT=$(git log --pretty=one "${DEBIAN_MASTER}" | \
    awk '
	/Ubuntu-/ {
		if (match($0, /UBUNTU: Ubuntu-/)) {
				print $1
				exit
                        }
                }
        '
)
if [ "${MASTER_COMMIT}" = "${BASE_COMMIT}" ]; then
	echo Already up to date.
	exit 0
fi

if [ -z "${MASTER_COMMIT}" ] || [ -z "${BASE_COMMIT}" ]; then
	echo "Could not find either master or base commit."
	echo "master commit: ${MASTER_COMMIT}"
	echo "base commit: ${BASE_COMMIT}"
	exit 1
fi

MASTER_VERSION=$(git show --format=%s -s "$MASTER_COMMIT" | sed 's/^UBUNTU: //')
BASE_VERSION=$(git show --format=%s -s "$BASE_COMMIT" | sed 's/^UBUNTU: //')
echo "Rebase still needed between $BASE_VERSION and $MASTER_VERSION."

if [ "${DRY_RUN}" ]; then
	echo "DRY RUN: git rebase --onto ${MASTER_COMMIT} ${BASE_COMMIT}"
	exit 0
fi

git rebase --onto "${MASTER_COMMIT}" "${BASE_COMMIT}"