bin/linux-pr

#!/usr/bin/env bash
# SPDX-License-Identifier: GPL-2.0-or-later
# Copyright (c) Jarkko Sakkinen 2025

set -e

SOURCE="git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd.git"
TEMPLATE_DIR="${XDG_DATA_HOME:-$HOME/.local/share}/linux-pr"

usage() {
  echo "Usage: $0 [-n|--dry-run] [-C <linux kernel tree>] [--postfix <postfix>] [--data-dir <data dir>] <template name> <version>"
}

git_kernel() {
  git -C "$kernel_tree" "$@"
}

render_template() {
  jq \
    --rawfile template "$template" \
    --arg tag "$tag" \
    --arg version "$version" \
    --arg pull_request "$pull_request" \
    --arg sender "$sender" \
    --arg sender_email "$sender_email" \
    --arg timestamp "$timestamp" \
    -rn '
      $template
      | gsub("{{sender}}"; $sender)
      | gsub("{{sender_email}}"; $sender_email)
      | gsub("{{timestamp}}"; $timestamp)
      | gsub("{{tag}}"; $tag)
      | gsub("{{version}}"; $version)
      | sub("{{pull_request}}"; $pull_request)
    '
}

kernel_tree=.
dry_run=
postfix=
data_dir="$TEMPLATE_DIR"

while [[ $# -gt 0 ]]; do
  case "$1" in
    -n|--dry-run)
      dry_run=1
      shift
      ;;
    -C)
      if [[ $# -lt 2 ]]; then
        usage >&2
        exit 1
      fi
      kernel_tree="$2"
      shift 2
      ;;
    --postfix)
      if [[ $# -lt 2 || -z "$2" ]]; then
        usage >&2
        exit 1
      fi
      postfix="$2"
      shift 2
      ;;
    --data-dir)
      if [[ $# -lt 2 || -z "$2" ]]; then
        usage >&2
        exit 1
      fi
      data_dir="$2"
      shift 2
      ;;
    -h|--help)
      usage
      exit 0
      ;;
    --)
      shift
      break
      ;;
    -*)
      echo "Unknown option: $1" >&2
      usage >&2
      exit 1
      ;;
    *)
      break
      ;;
  esac
done

if [[ -z "$kernel_tree" || $# -ne 2 ]]; then
  usage >&2
  exit 1
fi

if ! git -C "$kernel_tree" rev-parse --show-toplevel >/dev/null 2>&1; then
  echo "\"$kernel_tree\" is not a git repository" >&2
  exit 1
fi

template_name="$1"
version="$2"
if [[ -z "$template_name" || "$template_name" == */* ]]; then
  echo "Invalid template name: \"$template_name\"" >&2
  exit 1
fi
template="$data_dir/$template_name.mbox.in"
if [[ ! -f "$template" || ! -r "$template" ]]; then
  echo "Template \"$template_name\" not found or unreadable: $template" >&2
  exit 1
fi
tag="${template_name}-${version}"
git_tag="${tag}${postfix:+-$postfix}"
tag_ref="refs/tags/$git_tag"

if git_kernel show-ref --verify --quiet "$tag_ref"; then
  echo "\"$git_tag\" pre-exists"
  exit 1
fi

if git_kernel ls-remote --exit-code --refs --tags origin "$tag_ref" >/dev/null 2>&1; then
  echo "\"origin/$git_tag\" pre-exists"
  exit 1
fi

sender_email="$(git_kernel config user.email)"
sender="$(git_kernel config user.name) <$sender_email>"
timestamp=$(date +"%a %b %e %H:%M:%S %Y")
pull_request='{{pull_request}}'
subject=$(render_template | jq -Rrs '
  split("\n\n")[0]
  | split("\n")[]
  | select(startswith("Subject: "))
  | ltrimstr("Subject: ")
')
if [[ -z "$subject" ]] || grep -Eq '\{\{[^}]+\}\}' <<< "$subject"; then
  echo "\"$template\" has a missing or unresolved subject" >&2
  exit 1
fi

if [[ -n "$dry_run" ]]; then
  request_ref="HEAD:$tag_ref"
  printf "Dry run: using '%s' as request-pull end ref\n" "$request_ref" >&2
  pull_request=$(git_kernel request-pull mainline/master "$SOURCE" "$request_ref" 2>/dev/null) || true
  if [[ -z "$pull_request" ]]; then
    git_kernel request-pull mainline/master "$SOURCE" "$request_ref" >/dev/null
  fi
else
  request_ref="$git_tag"
  git_kernel tag -s --edit -m "$subject" -m "Signed-off-by: $sender" "$git_tag"
  git_kernel push origin "$git_tag"

  printf "Waiting for '%s'" "$git_tag" >&2
  while ! git ls-remote --exit-code --refs --tags "$SOURCE" "$tag_ref" >/dev/null 2>&1; do
    printf "." >&2
    sleep 1
  done
  printf " found\n" >&2

  pull_request=$(git_kernel request-pull mainline/master "$SOURCE" "$request_ref")
fi
output="git-pull-${tag}.mbox"
tmp_output="$(mktemp "${output}.XXXXXX")"

trap 'rm -f "$tmp_output"' EXIT

render_template > "$tmp_output"

if grep -Eq '\{\{[^}]+\}\}' "$tmp_output"; then
  echo "\"$template\" contains unresolved placeholders" >&2
  exit 1
fi

mv "$tmp_output" "$output"
trap - EXIT