core/systemd/systemd.install

#!/bin/bash

sd_booted() {
  [[ -d run/systemd/system && ! -L run/systemd/system ]]
}

add_journal_acls() {
  # ignore errors, since the filesystem might not support ACLs
  setfacl -Rnm g:wheel:rx,d:g:wheel:rx,g:adm:rx,d:g:adm:rx var/log/journal/ 2>/dev/null
  :
}

maybe_reexec() {
  if sd_booted; then
    systemctl --system daemon-reexec
  fi
}

post_common() {
  systemd-sysusers
  journalctl --update-catalog
}

_216_changes() {
  # create at least the symlink from /etc/os-release to /usr/lib/os-release
  systemd-tmpfiles --create etc.conf

  echo ':: Coredumps are handled by systemd by default. Collection behavior can be'
  echo '   tuned in /etc/systemd/coredump.conf.'
}

_219_changes() {
  if mkdir -m2755 var/log/journal/remote 2>/dev/null; then
    chgrp systemd-journal-remote var/log/journal/remote
  fi

  if ! systemctl is-enabled -q remote-fs.target; then
    systemctl enable -q remote-fs.target
  fi
}

post_install() {
  systemd-machine-id-setup

  post_common "$@"

  add_journal_acls

  # enable some services by default, but don't track them
  systemctl enable getty@tty1.service remote-fs.target

  # group 'systemd-journal-remote' is created by systemd-sysusers
  mkdir -m2755 var/log/journal/remote
  chgrp systemd-journal-remote var/log/journal/remote
}

post_upgrade() {
  post_common "$@"

  maybe_reexec "$@"

  local v upgrades=(216
                    219
  )

  for v in "${upgrades[@]}"; do
    if [[ $(vercmp "$v" "$2") -eq 1 ]]; then
      "_${v//-/_}_changes"
    fi
  done
}