#!/bin/sh

LOCKFILE=/var/lock/ghc-doc-index.lock

# the lockfile is not meant to be perfect, it's just in case

# two cron scripts get run close to each other to keep

# them from stepping on each other's toes.

if [ -f $LOCKFILE ]; then

  echo "Locked with $LOCKFILE"

  exit 0

fi

if [ "$(id -u)" != "0" ]; then

  echo Need to be root!

  exit 1

fi

trap "{ rm -f $LOCKFILE ; exit 255; }" EXIT

touch $LOCKFILE

PKGDIRCACHE=/var/lib/ghc/pkg-dir.cache

LISTING="env LANG=C ls -dl"

# only re-index ghc docs when there are changes

cd /usr/share/doc/ghc/html/libraries

if [ -r "$PKGDIRCACHE" ]; then

  $LISTING */ > $PKGDIRCACHE.new

  DIR_DIFF=$(diff $PKGDIRCACHE $PKGDIRCACHE.new)

else

  $LISTING */ > $PKGDIRCACHE

fi

if [ -x "gen_contents_index" -a ! -r "$PKGDIRCACHE.new" -o -n "$DIR_DIFF" ]; then

  ./gen_contents_index

fi

if [ -f $PKGDIRCACHE.new ]; then

  mv -f $PKGDIRCACHE.new $PKGDIRCACHE

fi