#! /bin/sh
# $Id: cvs-mirror,v 1.7 2000/09/14 15:05:22 john Exp john $

## configuration

diff=diff

# GNU patch is terminally fucked, but solaris version is even worse :-(
patch=patch

## variables

local_opts=""
remote_opts=""
update_remote=no

opt_verbose=yes

## functions

usage () {
  cat <<EOF
usage: cvs-mirror [OPTIONS..] LOCAL-DIR REMOTE-DIR

Mirror the local CVS tree checked out into the LOCAL-DIR directory to
the remote CVS tree that is checked out into REMOTE-DIR, updating the
remote repository.

OPTIONS may be any of:

	-l LOCAL-OPTS		Global options for CVS commands
	-r REMOTE-OPTS

	-f			Force updating of the remote repository
	-q			Quiet output
	-v			Verbose output
	-d			Debugging output

EOF
}

absolutify () {
  f=$1
  case "$f" in
    /*)
      ;;
    *)
      f="`pwd`/$f"
      ;;
  esac
  echo $f
}

print () {
  if [ $opt_verbose = yes ]; then
    printf "$1"
  fi
}

## entry point

while getopts l:r:fvd c; do
  case $c in
    l)
      local_opts=$OPTARG
      ;;
    r)
      remote_opts=$OPTARG
      ;;
    f)
      update_remote=yes
      ;;
    v)
      opt_verbose=yes
      ;;
    d)
      set -x
      ;;
    \?)
      usage
      exit 0
      ;;
  esac
done
shift `expr $OPTIND - 1`

[ $# -eq 2 ] || ( usage ; exit 1 )

local=`absolutify "$1"`
remote=`absolutify "$2"`

print "\n  local: $local\n  remote:  $remote\n"

print "\n* updating the copy of the local tree\n"
out=`( cd "$local" \
       && cvs $local_opts update . 2>/dev/null )`

if [ $update_remote = no ]; then
  # did any files change since last mirroring
  if echo "$out" | grep '^[ARUP]' >/dev/null; then
    update_remote=yes
  fi
  # sanity check
  if echo "$out" | grep '^[\?CM]' >/dev/null; then
    echo "warning: local repository has been modified!"
    exit 1
  fi
fi

# do we need to update the remote repository?
if [ $update_remote = yes ]; then
  print "\n* patching the copy of the remote tree\n"
  ( cd $local && $diff -urN -xCVS -L/dev/null $remote . ) \
      | ( cd $remote && $patch -p0 ) \
      || exit 1

  print "\n* scanning remote tree for changes\n"
  upd_out=`( cd $remote && cvs $remote_opts -n upd . 2>/dev/null )`

  deleted=`echo "$upd_out" | grep '^U ' | sed -e 's/^U \(.*\)$/\1/'`
  for f in $deleted; do
    print "** removing $f\n"
    ( cd $remote/`dirname $f` \
	&& cvs $remote_opts rm -f `basename $f` ) || exit 1
  done

  for f in `echo "$upd_out" | grep '^[\?]' | sed -e 's/^\? \(.*\)$/\1/'`; do
    print "** adding $f\n"
    ( cd $remote/`dirname $f` \
	&& cvs $remote_opts add -kb `basename $f` ) || exit 1
  done

  print "\n* committing the new remote tree\n"
  ( cd $remote && cvs $remote_opts commit -m "" . ) || exit 1
fi