scripts: add a helper for port-based MFC workflow

scripts/port_dir_mfc.sh

@@ -0,0 +1,78 @@
+#!/bin/sh
+
+# Copyright (c) 2024 Franco Fichtner <franco@opnsense.org>
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+#
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+
+set -e
+
+DIR=${1:-.}
+BRANCH=${2:-master}
+FROM=FreeBSD
+
+if git diff --quiet ${BRANCH} ${DIR}; then
+	echo ">>> Cherry-pick already complete."
+	exit 0
+fi
+
+echo -n ">>> Run a git-cherry-pick or raw merge? [r/G]: "
+
+read YN < /dev/tty
+case ${YN} in
+[rR])
+	git diff -R ${BRANCH} ${DIR} | git apply
+	git add ${DIR}
+	git commit -m \
+"${DIR}: sync with upstream
+
+Taken from: ${FROM}"
+	exit 0
+	;;
+*)
+	# FALLTHROUGH
+	;;
+esac
+
+COMMITS=
+
+for HASH in $(git log --oneline ${BRANCH} ${DIR} | awk '{ print $1 }'); do
+	if git diff --quiet ${HASH} ${DIR}; then
+		# found no more changes
+		break
+	fi
+
+	# reverse commit order for cherry-pick
+	COMMITS="${HASH} ${COMMITS}"
+done
+
+for COMMIT in ${COMMITS}; do
+	git cherry-pick ${COMMIT} || git cherry-pick --skip
+done
+
+if ! git diff --quiet ${BRANCH} ${DIR}; then
+	echo ">>> Cherry-pick failed due to non-emtpy diff." >&2
+	exit 1
+fi
+
+echo ">>> Cherry-pick finished successfully."