#!/bin/sh
# archive, unarchive -- tar and compress source for archival storage
command=`basename $0`

#-- parse command line options
set -- `getopt 'dlrtuvzZ' $*`
if [ $? != 0 ]
then
	cat <<eof/
Usage: $command [-d] [-r] [-t] [-u] [-v] [-z] [-Z] [archive_name]

Options:
  -d     debug
  -l     list-only (don't extract files)
  -r     remove directory (leave tar in parent)
  -t     touch archive (latest file)
  -u     un archive
  -v     verbose (lists filenames)
  -z     force suffix to .tar.gz (gzip)
  -Z     use compress rather than gzip

Parameters:
    archive_name   name for archive (default is current directory name)
eof/
	exit 1
fi

debug="eval"
extract="-xp"
listonly=""
remove="n"
touch="n"
unarchive="n"
verbose=""
suffix="tgz"
compress="gzip"

while [ $# != 0 ]
do
	opt=$1
	shift
	case $opt in
	-d)	debug="echo";;
	-l)	extract="-tv"; listonly="#";;
	-r)	remove="y";;
	-t)	touch="y";;
	-u)	unarchive="y";;
	-v)	verbose="-v";;
	-z)	compress="gzip";suffix=".tar.gz";;
	-Z)	compress="compress";suffix=".tar.Z";;
	--)	break;;
	esac
done

#-- if script is invoked as 'unarchive' do same as -u option
if [ $command = unarchive ]
then	unarchive="y"
fi

#-- figure out where we are
paths=`/bin/pwd`

#-- Provide default archive-name
if [ $# = 1 ]
then	dir=$1
	arg=$1
else	dir=`basename $paths`
	arg=.
fi

#-- Strip off known suffixes, to simplify passing archive-name
for suf in .tar.gz .tgz .tar.Z
do
	pre=`basename $dir $suf`
	if [ ".$pre" != ".$dir" ]
	then	dir=$pre
		break
	fi
done

if [ $unarchive = "y" ]
then
	if [ -f $dir.tar.gz ]
	then	decomp="gzip -d"
		myfile=$dir.tar.gz
	elif [ -f $dir.tgz ]
	then	decomp="gzip -d"
		myfile=$dir.tgz
	elif [ -f $dir.tar.Z ]
	then	decomp="uncompress"
		myfile=$dir.tar.Z
	else	echo "No archive $dir.tgz, $dir.tar.gz or $dir.tar.Z present."
		exit 1
	fi

	if [ ! -w . -a ".$listonly" = "." ]
	then
		$debug "chmod u+w ."
		if [ $? != 0 ]
		then
			echo "archive: chmod error"
			exit 1
		fi
	fi

	#-- uncompress and untar
	if [ ".$listonly" = "." ]
	then
		$debug	"mv $myfile .."
		$debug	myfile="../$myfile"
		if [ $? != 0 ]
		then
			echo "archive: mv error"
			exit 1
		fi
	fi

	$debug	"umask 0;$decomp -c $myfile | tar ${extract}${verbose}f - 2>&1"
	if [ $? != 0 ]
	then
		echo "archive: $decomp/tar error"
		exit 1
	fi

	#-- remove archive
	if [ ".$listonly" = "." ]
	then
		$debug	"rm -f $myfile"
	fi

elif [ ".$listonly" != "." ]
then	echo "archive: -l option applies only to dearchiving"
	exit 1
else
	if [ -f $dir.$suffix ]
	then
		echo "Archive $dir.$suffix already present."
		exit 1
	fi

	if [ $arg = . ]
	then	all='`ls -A`'
	else	all='`ls -Ad '$arg'`'
	fi
	$debug	"tar -c${verbose}f - $all | $compress -c >../$dir.$suffix"
	if [ $? != 0 ]
	then
		echo "archive: tar error"
		exit 1
	fi

	#-- obtain date for "-t" option
	if [ $touch = "y" ]
	then
		last=`find $arg -type f -print`
		if [ ".$last" != "." ]
		then
			last=`ls -1t $last | head -1`
			$debug cpd $last ../$dir.$suffix
			if [ ".$verbose" = ".v" ]; then echo last=$last;fi
		fi
	fi

	#-- remove current sources
	$debug	"chmod u+w ."
	$debug	"find $arg -type d -exec chmod u+w {} \\;"
	$debug	"rm -rf $all"

	if [ $remove = "y" ]
	then	#-- move archive to parent, removing leaf
		leaf=`basename $paths`
		$debug	"cd ..;rmdir $leaf"
	else	#-- move archive back in
		$debug	"mv ../$dir.$suffix ."
		if [ "$arg" = "." ]
		then
			$debug	"chmod -w ."
		fi
		if [ $touch = "y" ]
		then
			$debug cpd $dir.$suffix .
		fi
	fi
fi