future-install-scripts/pacstrap.in

#!/bin/bash

#
# Assumptions:
#  1) User has partitioned, formatted, and mounted partitions on /mnt
#  2) Network is functional
#  3) Arguments passed to the script are valid pacman targets
#  4) A valid mirror appears in /etc/pacman.d/mirrorlist
#

shopt -s extglob

# m4_include() is recognized as a function definition
# shellcheck source=common disable=SC1073,SC1065,SC1064,SC1072
m4_include(common)

hostcache=0
copykeyring=1
initkeyring=0
copymirrorlist=1
copyconfig=0
pacman_config=/etc/pacman.conf
pacman_args=()
pacmode='-Sy'
setup=chroot_setup
unshare=0

usage() {
  cat <<EOF
usage: ${0##*/} [options] root [packages...]

  Options:
    -C <config>    Use an alternate config file for pacman
    -c             Use the package cache on the host, rather than the target
    -D             Skip pacman dependency checks
    -G             Avoid copying the host's pacman keyring to the target
    -i             Prompt for package confirmation when needed (run interactively)
    -K             Initialize an empty pacman keyring in the target (implies '-G')
    -M             Avoid copying the host's mirrorlist to the target
    -N             Run in unshare mode as a regular user
    -P             Copy the host's pacman config to the target
    -U             Use 'pacman -U' to install packages

    -h             Print this help message

pacstrap installs packages to the specified new root directory.
If no packages are given, pacstrap defaults to the 'base' metapackage.

EOF
}

if [[ -z $1 || $1 = @(-h|--help) ]]; then
  usage
  exit $(( $# ? 0 : 1 ))
fi

while getopts ':C:cDGiKMNPU' flag; do
  case $flag in
    C)
      pacman_config="$OPTARG"
      ;;
    c)
      hostcache=1
      ;;
    D)
      pacman_args+=(-dd)
      ;;
    G)
      copykeyring=0
      ;;
    i)
      interactive=1
      ;;
    K)
      initkeyring=1
      ;;
    M)
      copymirrorlist=0
      ;;
    N)
      setup=unshare_setup
      unshare=1
      ;;
    P)
      copyconfig=1
      ;;
    U)
      pacmode='-U'
      ;;
    :)
      die "%s: option requires an argument -- '%s'" "${0##*/}" "$OPTARG"
      ;;
    ?)
      die "%s: invalid option -- '%s'" "${0##*/}" "$OPTARG"
      ;;
  esac
done
shift $(( OPTIND - 1 ))

(( $# )) || die 'No root directory specified'
newroot="$1"; shift
[[ -d "$newroot" ]] || die '%s: not a directory' "$newroot"

pacman_args+=("$pacmode" "${@:-base}" --config="$pacman_config")

if (( ! interactive )); then
  pacman_args+=(--noconfirm)
fi

set -e
gpgdir="$(pacman-conf --config="$pacman_config" GPGDir)"
cachedir="$(pacman-conf --config="$pacman_config" CacheDir)"
if (( copyconfig )); then
  dbpath="$newroot$(pacman-conf --config="$pacman_config" DBPath)"
  logfile="$newroot$(pacman-conf --config="$pacman_config" LogFile)"
  cachedir_target="$newroot$cachedir"
  gpgdir_target="$newroot$gpgdir"

  pacman_args+=(--dbpath="$dbpath" --logfile="$logfile")
else
  dbpath="$newroot"/var/lib/pacman
  logfile="$newroot"/var/log/pacman.log
  cachedir_target="$newroot"/var/cache/pacman/pkg
  gpgdir_target="$newroot"/etc/pacman.d/gnupg
fi

if (( ! hostcache )); then
  cachedir="$cachedir_target"
fi
pacman_args+=(--cachedir="$cachedir")
set +e

pacstrap() {
  check_root

  # create obligatory directories
  msg 'Creating install root at %s' "$newroot"
  mkdir -m 0755 -p "$dbpath" "$cachedir_target" "$(dirname "$logfile")" "$newroot"/{dev,run,etc/pacman.d}
  mkdir -m 1777 -p "$newroot"/tmp
  mkdir -m 0555 -p "$newroot"/{sys,proc}

  # mount API filesystems
  $setup "$newroot"

  if [[ ! -d "$gpgdir_target" ]]; then
    if (( initkeyring )); then
      pacman-key --gpgdir "$gpgdir_target" --init
    elif (( copykeyring )) && [[ -d "$gpgdir" ]]; then
      # if there's a keyring on the host, copy it into the new root
      cp -aT --no-preserve=ownership "$gpgdir" "$gpgdir_target"
    fi
  fi

  msg 'Installing packages to %s' "$newroot"
  $pid_unshare pacman --root "$newroot" "${pacman_args[@]}" || die 'Failed to install packages to new root'

  if (( copymirrorlist )); then
    # install the host's mirrorlist onto the new root
    cp -a /etc/pacman.d/mirrorlist "$newroot"/etc/pacman.d/ || warning "Failed to copy the host's mirrorlist to new root"
  fi

  if (( copyconfig )); then
    cp -a "$pacman_config" "$newroot"/etc/pacman.conf
  fi
}

if (( unshare )); then
  $mount_unshare bash -c "$(declare_all); pacstrap"
else
  pacstrap
fi

# vim: et ts=2 sw=2 ft=sh: