update_tor.sh

#!/bin/bash
# SPDX-License-Identifier: GPL-3.0-or-later
# set -x

# update Tor and restart Tor relay(s) under Gentoo Linux (OpenRC)

function restart() {
  export GRACEFUL_TIMEOUT=20

  # shellcheck disable=SC2011
  ls /etc/init.d/tor{,?} |
    xargs -n 1 basename |
    while read -r service; do
      echo
      echo "----------------------------"
      date
      echo " $service"
      echo

      if ! rc-service $service status; then
        echo -e "\n skipped"
      else
        if ! rc-service $service restart; then
          if pid=$(cat /run/tor/$service.pid); then
            if kill -0 $pid; then
              echo " kill pid $pid"
              kill -9 $pid
              sleep 1
            else
              rm /run/tor/$service.pid
              echo " stale pid $pid"
            fi
          fi
          if ! rc-service $service zap start; then
            echo "zap start failed"
          fi
        fi
      fi
      echo
    done
}

#######################################################################
set -eu
export LANG=C.utf8
export PATH="/usr/sbin:/usr/bin:/sbin:/bin"

export GIT_PAGER="cat"

if [[ ! -d ~/tor ]]; then
  cd ~
  git clone https://git.torproject.org/tor.git/

# any parameter forces a rebuild
elif [[ $# -eq 0 ]]; then
  tmpfile=$(mktemp /tmp/$(basename $0)_XXXXXX.tmp)
  cd ~/tor
  git pull &>$tmpfile
  range=$(grep -e "^Updating .*\.\..*$" $tmpfile | cut -f 2 -d ' ' -s)
  if [[ -n $range ]]; then
    cat $tmpfile
    echo
    git log $range
    echo

    rm $tmpfile
  else
    rm $tmpfile
    # detect the need of a rebuild if e.g. libevent was updated and tor therefore refuses even to start
    # plus: if git pull succeeded but a subsequent emerge failed, then this would give a version versus commit id mismatch
    if tor --version | grep -q $(git show --quiet --oneline 'HEAD' | cut -f 1 -d ' '); then
      exit 0
    fi
  fi
fi

echo
date
emerge -1 net-vpn/tor

restart

echo
date
echo " all work done"