update

#!/bin/bash

set -e -o pipefail
shopt -s dotglob extglob nullglob
cd -- "$(git -C "${0%/*}" rev-parse --show-toplevel)"

if [[ $@ != @(+([0-9a-f])|master) ]]; then
  echo "Usage: ${0##*/} ( COMMIT | master )"
  echo "Update upstream branch then merge changes into master."
  echo "This maintainer script does not attempt to be portable."
  exit 64
elif ! git diff --exit-code --quiet; then
  echo "Uncommitted changes in the working directory"
  exit 1
elif ! git diff --cached --exit-code --quiet; then
  echo "Uncommitted changes in the index"
  exit 1
fi >&2

TMP=$(mktemp -d tmp-XXXXXX)
trap 'rm -r $TMP' EXIT

echo "Cloning upstream sources for sparse checkout:"
git clone --no-checkout --filter=blob:none  --shallow-since '6 months' \
  https://github.com/openbsd/src $TMP
git -C $TMP sparse-checkout set lib/libutil sys/sys usr.sbin/ntpd
git -C $TMP checkout -q $1

git checkout upstream
git rm -q -r src
mkdir -p src

for FILE in $TMP/lib/libutil/imsg{,-buffer}.[ch] $TMP/sys/sys/queue.h \
    $TMP/usr.sbin/ntpd/*.[chy58]; do
  sed ':a;s/[ \t]*$//;/^\n*$/{$d;N;ba}' "$FILE" \
    | unexpand >"src/${FILE##*/}"
  git add "src/${FILE##*/}"
done

mkdir -p man openbsd
git mv -f src/*.[58] man
git mv -f src/sensors.c openbsd

if git diff --cached --exit-code --quiet; then
  echo "No upstream changes to merge"
  git checkout master
else
  SNAPSHOT=$(git -C $TMP log -1 --abbrev=8 --pretty='%cs (%h)')
  git commit -m "Update upstream files from OpenBSD $SNAPSHOT"
  git checkout master
  git merge -m "Merge from upstream OpenBSD $SNAPSHOT" upstream

  echo "Merged openntpd ready to review, build and test"
  echo "Sign: git tag -m openntpd-VERSION -s openntpd-VERSION"
  echo "Push: git push --tags origin upstream master"
fi