path: root/scripts/repo-add.sh.in

#!/bin/bash
#
#   repo-add - add a package to a given repo database file
#   repo-remove - remove a package entry from a given repo database file
#   @configure_input@
#
#   Copyright (c) 2006-2014 Pacman Development Team <pacman-dev@archlinux.org>
#
#   This program is free software; you can redistribute it and/or modify
#   it under the terms of the GNU General Public License as published by
#   the Free Software Foundation; either version 2 of the License, or
#   (at your option) any later version.
#
#   This program is distributed in the hope that it will be useful,
#   but WITHOUT ANY WARRANTY; without even the implied warranty of
#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#   GNU General Public License for more details.
#
#   You should have received a copy of the GNU General Public License
#   along with this program.  If not, see <http://www.gnu.org/licenses/>.

shopt -s extglob

# gettext initialization
export TEXTDOMAIN='pacman-scripts'
export TEXTDOMAINDIR='@localedir@'

declare -r myver='@PACKAGE_VERSION@'
declare -r confdir='@sysconfdir@'

QUIET=0
DELTA=0
ONLYADDNEW=0
RMEXISTING=0
WITHFILES=0
SIGN=0
VERIFY=0
REPO_DB_FILE=
LOCKFILE=
CLEAN_LOCK=0
USE_COLOR='y'

# ensure we have a sane umask set
umask 0022

m4_include(library/output_format.sh)

# print usage instructions
usage() {
  cmd=${0##*/}
  printf -- "%s (pacman) %s\n\n" "$cmd" "$myver"
  if [[ $cmd == "repo-add" ]] ; then
    printf -- "$(gettext "Usage: repo-add [options] <path-to-db> <package|delta> ...\n")"
    printf -- "\n"
    printf -- "$(gettext "\
repo-add will update a package database by reading a package file.\n\
Multiple packages to add can be specified on the command line.\n")"
    printf -- "\n"
    printf -- "$(gettext "Options:\n")"
    printf -- "$(gettext "  -d, --delta       generate and add delta for package update\n")"
    printf -- "$(gettext "  -n, --new         only add packages that are not already in the database\n")"
    printf -- "$(gettext "  -R, --remove      remove package file from disk when updating database entry\n")"
    printf -- "$(gettext "  -f, --files       update database's file list\n")"
  elif [[ $cmd == "repo-remove" ]] ; then
    printf -- "$(gettext "Usage: repo-remove [options] <path-to-db> <packagename|delta> ...\n")"
    printf -- "\n"
    printf -- "$(gettext "\
repo-remove will update a package database by removing the package name\n\
specified on the command line from the given repo database. Multiple\n\
packages to remove can be specified on the command line.\n")"
    printf -- "\n"
    printf -- "$(gettext "Options:\n")"
  else
    printf -- "$(gettext "Please move along, there is nothing to see here.\n")"
    return
  fi
  printf -- "$(gettext "  --nocolor         turn off color in output\n")"
  printf -- "$(gettext "  -q, --quiet       minimize output\n")"
  printf -- "$(gettext "  -s, --sign        sign database with GnuPG after update\n")"
  printf -- "$(gettext "  -k, --key <key>   use the specified key to sign the database\n")"
  printf -- "$(gettext "  -v, --verify      verify database's signature before update\n")"
  printf -- "$(gettext "\n\
See %s(8) for more details and descriptions of the available options.\n")" $cmd
  printf "\n"
  if [[ $cmd == "repo-add" ]] ; then
    printf -- "$(gettext "Example:  repo-add /path/to/repo.db.tar.gz pacman-3.0.0-1-i686.pkg.tar.gz\n")"
  elif [[ $cmd == "repo-remove" ]] ; then
    printf -- "$(gettext "Example:  repo-remove /path/to/repo.db.tar.gz kernel26\n")"
  fi
}

version() {
  cmd=${0##*/}
  printf "%s (pacman) %s\n\n" "$cmd" "$myver"
  printf -- "$(gettext "\
Copyright (c) 2006-2014 Pacman Development Team <pacman-dev@archlinux.org>\n\n\
This is free software; see the source for copying conditions.\n\
There is NO WARRANTY, to the extent permitted by law.\n")"
}

# format a metadata entry
#   arg1 - Entry name
#   ...  - value(s)
format_entry() {
  local field=$1; shift

  if [[ $1 ]]; then
    printf '%%%s%%\n' "$field"
    printf '%s\n' "$@"
    printf '\n'
  fi
}

find_pkgentry() {
  local pkgname=$1
  local pkgentry
  for pkgentry in "$tmpdir/tree/$pkgname"*; do
    name=${pkgentry##*/}
    if [[ ${name%-*-*} = $pkgname ]]; then
      echo $pkgentry
      return 0
    fi
  done
  return 1
}

# Get the package name from the delta filename
get_delta_pkgname() {
  local tmp

  tmp=${1##*/}
  echo ${tmp%-*-*_to*}
}

# write a delta entry
#   arg1 - path to delta file
db_write_delta() {
  deltafile=$1
  pkgname=$(get_delta_pkgname "$deltafile")

  pkgentry=$(find_pkgentry "$pkgname")
  if [[ -z $pkgentry ]]; then
    error "$(gettext "No database entry for package '%s'.")" "$pkgname"
    return 1
  fi
  deltas=$pkgentry/deltas
  if [[ ! -f $deltas ]]; then
    echo -e "%DELTAS%" >"$deltas"
  fi
  # get md5sum and compressed size of package
  md5sum=$(openssl dgst -md5 "$deltafile")
  md5sum=${md5sum##* }
  csize=$(@SIZECMD@ -L "$deltafile")

  oldfile=$(xdelta3 printhdr "$deltafile" | grep "XDELTA filename (source)" | sed 's/.*: *//')
  newfile=$(xdelta3 printhdr "$deltafile" | grep "XDELTA filename (output)" | sed 's/.*: *//')

  if grep -q "$oldfile.*$newfile" "$deltas"; then
    sed -i.backup "/$oldfile.*$newfile/d" "$deltas" && rm -f "$deltas.backup"
  fi
  msg2 "$(gettext "Adding 'deltas' entry : %s -> %s")" "$oldfile" "$newfile"
  echo "${deltafile##*/} $md5sum $csize $oldfile $newfile" >> "$deltas"

  return 0
} # end db_write_delta

# remove a delta entry
#   arg1 - path to delta file
db_remove_delta() {
  deltafile=$1
  filename=${deltafile##*/}
  pkgname=$(get_delta_pkgname "$deltafile")

  pkgentry=$(find_pkgentry "$pkgname")
  if [[ -z $pkgentry ]]; then
    return 1
  fi
  deltas=$pkgentry/deltas
  if [[ ! -f $deltas ]]; then
    return 1
  fi
  if grep -q "$filename" "$deltas"; then
    sed -i.backup "/$filename/d" "$deltas" && rm -f "$deltas.backup"
    msg2 "$(gettext "Removing existing entry '%s'...")" "$filename"
    # empty deltas file contains only "%DELTAS%"
    if (( $(wc -l < "$deltas") == 1 )); then
      msg2 "$(gettext "Removing empty deltas file ...")"
      rm "$deltas"
    fi
    return 0
  fi

  return 1
} # end db_remove_delta

check_gpg() {
  if ! type -p gpg >/dev/null; then
    error "$(gettext "Cannot find the gpg binary! Is GnuPG installed?")"
    exit 1 # $E_MISSING_PROGRAM
  fi
}

# sign the package database once repackaged
create_signature() {
  (( ! SIGN )) && return
  local dbfile=$1
  local ret=0
  msg "$(gettext "Signing database...")"

  local SIGNWITHKEY=""
  if [[ -n $GPGKEY ]]; then
    SIGNWITHKEY="-u ${GPGKEY}"
  fi
  gpg --detach-sign --use-agent ${SIGNWITHKEY} "$dbfile" &>/dev/null || ret=$?

  if (( ! ret )); then
    msg2 "$(gettext "Created signature file '%s'")" "${dbfile##*/.tmp.}.sig"
  else
    warning "$(gettext "Failed to sign package database.")"
  fi
}

# verify the existing package database signature
verify_signature() {
  (( ! VERIFY )) && return
  local dbfile=$1
  local ret=0
  msg "$(gettext "Verifying database signature...")"

  if [[ ! -f $dbfile.sig ]]; then
    warning "$(gettext "No existing signature found, skipping verification.")"
    return
  fi
  gpg --verify "$dbfile.sig" || ret=$?
  if (( ! ret )); then
    msg2 "$(gettext "Database signature file verified.")"
  else
    error "$(gettext "Database signature was NOT valid!")"
    exit 1
  fi
}

verify_repo_extension() {
  local repofile=$1

  case $repofile in
    *.@(db|files).tar.gz)  TAR_OPT="z" ;;
    *.@(db|files).tar.bz2) TAR_OPT="j" ;;
    *.@(db|files).tar.xz)  TAR_OPT="J" ;;
    *.@(db|files).tar.Z)   TAR_OPT="Z" ;;
    *.@(db|files).tar)     TAR_OPT="" ;;
    *) error "$(gettext "'%s' does not have a valid archive extension.")" \
        "$repofile"
      exit 1 ;;
  esac

  printf '%s' "$TAR_OPT"
}

# write an entry to the pacman database
#   arg1 - path to package
db_write_entry() {
  # blank out all variables
  local pkgfile=$1
  local -a _groups _licenses _replaces _depends _conflicts _provides \
    _optdepends _makedepends _checkdepends
  local pkgname pkgver pkgdesc csize size url arch builddate packager \
    md5sum sha256sum pgpsig pgpsigsize

  # read info from the zipped package
  local line var val
  while read -r line; do
    [[ ${line:0:1} = '#' ]] && continue
    IFS=' =' read -r var val < <(printf '%s\n' "$line")

    # normalize whitespace with an extglob
    declare "$var=${val//+([[:space:]])/ }"
    case $var in
      group) _groups+=("$group") ;;
      license) _licenses+=("$license") ;;
      replaces) _replaces+=("$replaces") ;;
      depend) _depends+=("$depend") ;;
      conflict) _conflicts+=("$conflict") ;;
      provides) _provides+=("$provides") ;;
      optdepend) _optdepends+=("$optdepend") ;;
      makedepend) _makedepends+=("$makedepend") ;;
      checkdepend) _checkdepends+=("$checkdepend") ;;
    esac
  done< <(bsdtar -xOqf "$pkgfile" .PKGINFO)

  # ensure $pkgname and $pkgver variables were found
  if [[ -z $pkgname || -z $pkgver ]]; then
    error "$(gettext "Invalid package file '%s'.")" "$pkgfile"
    return 1
  fi

  if [[ -d $tmpdir/tree/$pkgname-$pkgver ]]; then
    warning "$(gettext "An entry for '%s' already existed")" "$pkgname-$pkgver"
    if (( ONLYADDNEW )); then
      return 0;
    fi
  else
    if (( DELTA )); then
      pkgentry=$(find_pkgentry "$pkgname")
      if [[ -n $pkgentry ]]; then
        local oldfilename=$(grep -A1 FILENAME "$pkgentry/desc" | tail -n1)
        local oldfile="$(dirname "$1")/$oldfilename"
      fi
    elif (( RMEXISTING )); then
      # only remove existing package if we're not doing deltas
      pkgentry=$(find_pkgentry "$pkgname")
      if [[ -n $pkgentry ]]; then
        local oldfilename="$(sed -n '/^%FILENAME%$/ {n;p;q;}' "$pkgentry/desc")"
        local oldfile="$(dirname "$1")/$oldfilename"
        msg2 "$(gettext "Removing existing package '%s'")" "$oldfilename"
        rm -f ${oldfile} ${oldfile}.sig
      fi
    fi
  fi

  # compute base64'd PGP signature
  if [[ -f "$pkgfile.sig" ]]; then
    pgpsigsize=$(@SIZECMD@ -L "$pkgfile.sig")
    if (( pgpsigsize > 16384 )); then
      error "$(gettext "Invalid package signature file '%s'.")" "$pkgfile.sig"
      return 1
    fi
    msg2 "$(gettext "Adding package signature...")"
    pgpsig=$(openssl base64 -in "$pkgfile.sig" | tr -d '\n')
  fi

  csize=$(@SIZECMD@ -L "$pkgfile")

  # compute checksums
  msg2 "$(gettext "Computing checksums...")"
  md5sum=$(openssl dgst -md5 "$pkgfile")
  md5sum=${md5sum##* }
  sha256sum=$(openssl dgst -sha256 "$pkgfile")
  sha256sum=${sha256sum##* }

  # remove an existing entry if it exists, ignore failures
  db_remove_entry "$pkgname"

  # create package directory
  pushd "$tmpdir/tree" >/dev/null
  mkdir "$pkgname-$pkgver"
  pushd "$pkgname-$pkgver" >/dev/null

  # restore an eventual deltas file
  [[ -f ../$pkgname.deltas ]] && mv "../$pkgname.deltas" deltas

  # create desc entry
  msg2 "$(gettext "Creating '%s' db entry...")" 'desc'
  {
    format_entry "FILENAME"  "${1##*/}"
    format_entry "NAME"      "$pkgname"
    format_entry "BASE"      "$pkgbase"
    format_entry "VERSION"   "$pkgver"
    format_entry "DESC"      "$pkgdesc"
    format_entry "GROUPS"    "${_groups[@]}"
    format_entry "CSIZE"     "$csize"
    format_entry "ISIZE"     "$size"

    # add checksums
    format_entry "MD5SUM"    "$md5sum"
    format_entry "SHA256SUM" "$sha256sum"

    # add PGP sig
    format_entry "PGPSIG"    "$pgpsig"

    format_entry "URL"       "$url"
    format_entry "LICENSE"   "${_licenses[@]}"
    format_entry "ARCH"      "$arch"
    format_entry "BUILDDATE" "$builddate"
    format_entry "PACKAGER"  "$packager"
    format_entry "REPLACES"  "${_replaces[@]}"
  } >'desc'

  # create depends entry
  msg2 "$(gettext "Creating '%s' db entry...")" 'depends'
  {
    format_entry "DEPENDS" "${_depends[@]}"
    format_entry "CONFLICTS" "${_conflicts[@]}"
    format_entry "PROVIDES" "${_provides[@]}"
    format_entry "OPTDEPENDS" "${_optdepends[@]}"
    format_entry "MAKEDEPENDS" "${_makedepends[@]}"
    format_entry "CHECKDEPENDS" "${_checkdepends[@]}"
  } >'depends'

  popd >/dev/null
  popd >/dev/null

  # create files file if wanted
  if (( WITHFILES )); then
    msg2 "$(gettext "Creating '%s' db entry...")" 'files'
    local files_path="$tmpdir/tree/$pkgname-$pkgver/files"
    echo "%FILES%" >"$files_path"
    bsdtar --exclude='^.*' -tf "$pkgfile" >>"$files_path"
  fi

  # create a delta file
  if (( DELTA )); then
    if [[ -n $oldfilename ]]; then
      if [[ -f $oldfile ]]; then
        delta=$(pkgdelta -q "$oldfile" "$1")
        if [[ -f $delta ]]; then
          db_write_delta "$delta"
        fi
      else
        warning "$(gettext "Old package file not found: %s")" "$oldfilename"
      fi
    fi
  fi

  return 0
} # end db_write_entry

# remove existing entries from the DB
#   arg1 - package name
db_remove_entry() {
  local pkgname=$1
  local notfound=1
  local pkgentry=$(find_pkgentry "$pkgname")
  while [[ -n $pkgentry ]]; do
    notfound=0
    if [[ -f $pkgentry/deltas ]]; then
      mv "$pkgentry/deltas" "$tmpdir/tree/$pkgname.deltas"
    fi
    msg2 "$(gettext "Removing existing entry '%s'...")" \
    "${pkgentry##*/}"
    rm -rf "$pkgentry"
    pkgentry=$(find_pkgentry "$pkgname")
  done
  return $notfound
} # end db_remove_entry

elephant() {
  case $(( RANDOM % 2 )) in
    0) printf '%s\n' "H4sIAL3qBE4CAyWLwQ3AMAgD/0xh5UPzYiFUMgjq7LUJsk7yIQNAQTAikFUDnqkr" \
                     "OQFOUm0Wd9pHCi13ONjBpVdqcWx+EdXVX4vXvGv5cgztB9+fJxZ7AAAA"
    ;;

    1) printf '%s\n' "H4sIAJVWBU4CA21RMQ7DIBDbeYWrDgQJ7rZ+IA/IB05l69alcx5fc0ASVXUk4jOO" \
                     "7yAAUWtorygwJ4hlMii0YkJKKRKGvsMsiykl1SalvrMD1gUXyXRkGZPx5OPft81K" \
                     "tNAiAjyGjYO47h1JjizPkJrCWbK/4C+uLkT7bzpGc7CT9bmOzNSW5WLSO5vexjmH" \
                     "ZL9JFFZeAa0a2+lKjL2anpYfV+0Zx9LJ+/MC8nRayuDlSNy2rfAPibOzsiWHL0jL" \
                     "SsjFAQAA"
    ;;
  esac | openssl base64 -d | gzip -d
}

check_repo_db() {
  local repodir

  # ensure the path to the DB exists; $LOCKFILE is always an absolute path
  repodir=${LOCKFILE%/*}/

  if [[ ! -d $repodir ]]; then
    error "$(gettext "%s does not exist or is not a directory.")" "$repodir"
    exit 1
  fi

  # check lock file
  if ( set -o noclobber; echo "$$" > "$LOCKFILE") 2> /dev/null; then
    CLEAN_LOCK=1
  else
    error "$(gettext "Failed to acquire lockfile: %s.")" "$LOCKFILE"
    [[ -f $LOCKFILE ]] && error "$(gettext "Held by process %s")" "$(cat "$LOCKFILE")"
    exit 1
  fi

  if [[ -f $REPO_DB_FILE ]]; then
    # there are two situations we can have here- a DB with some entries,
    # or a DB with no contents at all.
    if ! bsdtar -tqf "$REPO_DB_FILE" '*/desc' >/dev/null 2>&1; then
      # check empty case
      if [[ -n $(bsdtar -tqf "$REPO_DB_FILE" '*' 2>/dev/null) ]]; then
        error "$(gettext "Repository file '%s' is not a proper pacman database.")" "$REPO_DB_FILE"
        exit 1
      fi
    fi
    verify_signature "$REPO_DB_FILE"
    msg "$(gettext "Extracting database to a temporary location...")"
    bsdtar -xf "$REPO_DB_FILE" -C "$tmpdir/tree"
  else
    case $cmd in
      repo-remove)
      error "$(gettext "Repository file '%s' was not found.")" "$REPO_DB_FILE"
      exit 1
      ;;
      repo-add)
      # check if the file can be created (write permission, directory existence, etc)
      if ! touch "$REPO_DB_FILE"; then
        error "$(gettext "Repository file '%s' could not be created.")" "$REPO_DB_FILE"
        exit 1
      fi
      rm -f "$REPO_DB_FILE"
      ;;
    esac
  fi
}

add() {
  if [[ ! -f $1 ]]; then
    error "$(gettext "File '%s' not found.")" "$1"
    return 1
  fi

  if [[ ${1##*.} == "delta" ]]; then
    deltafile=$1
    msg "$(gettext "Adding delta '%s'")" "$deltafile"
    if ! type xdelta3 &>/dev/null; then
      error "$(gettext "Cannot find the xdelta3 binary! Is xdelta3 installed?")"
      exit 1
    fi
    if db_write_delta "$deltafile"; then
      return 0
    else
      return 1
    fi
  fi

  pkgfile=$1
  if ! bsdtar -tqf "$pkgfile" .PKGINFO >/dev/null 2>&1; then
    error "$(gettext "'%s' is not a package file, skipping")" "$pkgfile"
    return 1
  fi

  msg "$(gettext "Adding package '%s'")" "$pkgfile"

  db_write_entry "$pkgfile"
}

remove() {
  if [[ ${1##*.} == "delta" ]]; then
    deltafile=$1
    msg "$(gettext "Searching for delta '%s'...")" "$deltafile"
    if db_remove_delta "$deltafile"; then
      return 0
    else
      error "$(gettext "Delta matching '%s' not found.")" "$deltafile"
      return 1
    fi
  fi

  pkgname=$1
  msg "$(gettext "Searching for package '%s'...")" "$pkgname"

  if db_remove_entry "$pkgname"; then
    rm -f "$tmpdir/tree/$pkgname.deltas"
    return 0
  else
    error "$(gettext "Package matching '%s' not found.")" "$pkgname"
    return 1
  fi
}

trap_exit() {
  # unhook all traps to avoid race conditions
  trap '' EXIT TERM HUP QUIT INT ERR

  echo
  error "$@"
  clean_up 1
}

clean_up() {
  local exit_code=${1:-$?}

  # unhook all traps to avoid race conditions
  trap '' EXIT TERM HUP QUIT INT ERR

  [[ -d $tmpdir ]] && rm -rf "$tmpdir"
  (( CLEAN_LOCK )) && [[ -f $LOCKFILE ]] && rm -f "$LOCKFILE"

  exit $exit_code
}

# PROGRAM START

# determine whether we have gettext; make it a no-op if we do not
if ! type gettext &>/dev/null; then
  gettext() {
    echo "$@"
  }
fi

case $1 in
  -h|--help) usage; exit 0;;
  -V|--version) version; exit 0;;
esac

# figure out what program we are
cmd=${0##*/}
if [[ $cmd == "repo-elephant" ]]; then
  elephant
  exit 0
fi

if [[ $cmd != "repo-add" && $cmd != "repo-remove" ]]; then
  error "$(gettext "Invalid command name '%s' specified.")" "$cmd"
  exit 1
fi

tmpdir=$(mktemp -d "${TMPDIR:-/tmp}/repo-tools.XXXXXXXXXX") || (\
  error "$(gettext "Cannot create temp directory for database building.")"; \
  exit 1)
mkdir "$tmpdir/tree"

trap 'clean_up' EXIT
for signal in TERM HUP QUIT; do
  trap "trap_exit \"$(gettext "%s signal caught. Exiting...")\" \"$signal\"" "$signal"
done
trap 'trap_exit "$(gettext "Aborted by user! Exiting...")"' INT
trap 'trap_exit "$(gettext "An unknown error has occurred. Exiting...")"' ERR

declare -a args
success=0
# parse arguments
while (( $# )); do
  case $1 in
    -q|--quiet) QUIET=1;;
    -d|--delta) DELTA=1;;
    -n|--new) ONLYADDNEW=1;;
    -R|--remove) RMEXISTING=1;;
    -f|--files) WITHFILES=1;;
    --nocolor) USE_COLOR='n';;
    -s|--sign)
      check_gpg
      SIGN=1
      if ! gpg --list-key ${GPGKEY} &>/dev/null; then
        if [[ ! -z $GPGKEY ]]; then
          error "$(gettext "The key ${GPGKEY} does not exist in your keyring.")"
        else
          error "$(gettext "There is no key in your keyring.")"
        fi
        exit 1
      fi
      ;;
    -k|--key)
      check_gpg
      shift
      GPGKEY=$1
      if ! gpg --list-key ${GPGKEY} &>/dev/null; then
        error "$(gettext "The key ${GPGKEY} does not exist in your keyring.")"
        exit 1
      fi
      ;;
    -v|--verify)
      check_gpg
      VERIFY=1
      ;;
    *)
      args+=("$1")
      ;;
  esac
  shift
done

m4_include(library/term_colors.sh)

REPO_DB_FILE=${args[0]}
if [[ -z $REPO_DB_FILE ]]; then
  usage
  exit 1
fi

if [[ $REPO_DB_FILE == /* ]]; then
  LOCKFILE=$REPO_DB_FILE.lck
else
  LOCKFILE=$PWD/$REPO_DB_FILE.lck
fi

verify_repo_extension "$REPO_DB_FILE" >/dev/null
check_repo_db

for arg in "${args[@]:1}"; do
  case $cmd in
    repo-add) add "$arg" ;;
    repo-remove) remove "$arg" ;;
  esac && success=1
done

# if at least one operation was a success, re-zip database
if (( success )); then
  msg "$(gettext "Creating updated database file '%s'")" "$REPO_DB_FILE"

  TAR_OPT=$(verify_repo_extension "$REPO_DB_FILE")
  # $LOCKFILE is already guaranteed to be absolute so this is safe
  dirname=${LOCKFILE%/*}
  filename=${REPO_DB_FILE##*/}
  # this ensures we create it on the same filesystem, making moves atomic
  tempname=$dirname/.tmp.$filename

  pushd "$tmpdir/tree" >/dev/null
  if ( shopt -s nullglob; files=(*); (( ${#files[*]} )) ); then
    bsdtar -c${TAR_OPT}f "$tempname" *
  else
    # we have no packages remaining? zip up some emptyness
    warning "$(gettext "No packages remain, creating empty database.")"
    bsdtar -c${TAR_OPT}f "$tempname" -T /dev/null
  fi
  popd >/dev/null

  create_signature "$tempname"

  # hardlink or move the previous version of the database and signature to .old
  # extension as a backup measure
  if [[ -f $REPO_DB_FILE ]]; then
    ln -f "$REPO_DB_FILE" "$REPO_DB_FILE.old" 2>/dev/null || \
      mv -f "$REPO_DB_FILE" "$REPO_DB_FILE.old"
  fi
  if [[ -f $REPO_DB_FILE.sig ]]; then
    ln -f "$REPO_DB_FILE.sig" "$REPO_DB_FILE.old.sig" 2>/dev/null || \
      mv -f "$REPO_DB_FILE.sig" "$REPO_DB_FILE.old.sig"
  else
    rm -f "$REPO_DB_FILE.old.sig"
  fi

  # rotate the newly-created database and signature into place
  mv "$tempname" "$REPO_DB_FILE"
  if [[ -f $tempname.sig ]]; then
    mv "$tempname.sig" "$REPO_DB_FILE.sig"
  fi

  dblink=${REPO_DB_FILE%.tar*}
  rm -f "$dblink" "$dblink.sig"
  ln -s "$filename" "$dblink" 2>/dev/null || \
    ln "$filename" "$dblink" 2>/dev/null || \
    cp "$REPO_DB_FILE" "$dblink"
  if [[ -f "$REPO_DB_FILE.sig" ]]; then
    ln -s "$filename.sig" "$dblink.sig" 2>/dev/null || \
      ln "$filename.sig" "$dblink.sig" 2>/dev/null || \
      cp "$REPO_DB_FILE.sig" "$dblink.sig"
  fi
else
  msg "$(gettext "No packages modified, nothing to do.")"
  exit 1
fi

exit 0
# vim: set ts=2 sw=2 noet: