commit-msg

#!/bin/sh
# From Gerrit Code Review 3.5.0.1-1-g05e28e622e
#
# Part of Gerrit Code Review (https://www.gerritcodereview.com/)
#
# Copyright (C) 2009 The Android Open Source Project
#
# 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.

set -u

# avoid [[ which is not POSIX sh.
if test "$#" != 1; then
	echo "$0 requires an argument."
	exit 1
fi

if test ! -f "$1"; then
	echo "file does not exist: $1"
	exit 1
fi

# Do not create a change id if requested
if test "false" = "$(git config --bool --get gerrit.createChangeId)"; then
	exit 0
fi

if git rev-parse --verify HEAD >/dev/null 2>&1; then
	refhash="$(git rev-parse HEAD)"
else
	refhash="$(git hash-object -t tree /dev/null)"
fi

random=$({
	git var GIT_COMMITTER_IDENT
	echo "$refhash"
	cat "$1"
} | git hash-object --stdin)
dest="$1.tmp.${random}"

trap 'rm -f "${dest}"' EXIT

if ! git stripspace --strip-comments <"$1" >"${dest}"; then
	echo "cannot strip comments from $1"
	exit 1
fi

if test ! -s "${dest}"; then
	echo "file is empty: $1"
	exit 1
fi

reviewurl="$(git config --get gerrit.reviewUrl)"
if test -n "${reviewurl}"; then
	if ! git interpret-trailers --parse <"$1" | grep -q '^Link:.*/id/I[0-9a-f]\{40\}$'; then
		if ! git interpret-trailers \
			--trailer "Link: ${reviewurl%/}/id/I${random}" <"$1" >"${dest}"; then
			echo "cannot insert link footer in $1"
			exit 1
		fi
	fi
else
	# Avoid the --in-place option which only appeared in Git 2.8
	# Avoid the --if-exists option which only appeared in Git 2.15
	if ! git -c trailer.ifexists=doNothing interpret-trailers \
		--trailer "Change-Id: I${random}" <"$1" >"${dest}"; then
		echo "cannot insert change-id line in $1"
		exit 1
	fi
fi

if ! mv "${dest}" "$1"; then
	echo "cannot mv ${dest} to $1"
	exit 1
fi