sync2layer

#!/bin/bash
#Util to move files to second aufs layer
#VERSION 4.2

if [ -f $(dirname $0)/pfs ] ;  then
    . $(dirname $0)/pfs
else 
    . $(which pfs) || exit 13 
fi    

FILELIST=/.savelist
#changesDir=/memory/changes
rm -f /tmp/savelist* /tmp/allfiles /tmp/includedfiles /tmp/excludedfiles  

function help () {
echo "\
$(basename $0) -- this util move the files from upper system aufs layer to second layer
It helps you to clear tmpfs diskspace, or to save changes

Usage:
$(basename $0) <newlayer> 	- create new layer and move files
$(basename $0)	 	- move files to existing second aufs layer

If <newlayer> name has no extintion, $(basename $0) create directory-layer.
If <newlayer> has extintion \".rom\" $(basename $0) create fs in file layer (ext3).

Please edit file \"/.savelist\" to specifу files to move:
!/path/file - pattern to delete from white list
/path/file  - pattern to add back to white list from delete list
" 
exit 0
}

function dirlayer () {
[ -d $layername ] || mkdir -p $layername
cat /proc/mounts | grep -q "$layername" &&  exitmsg "$layername already mounted" 1
pfsload -u $layername
}

function filelayer () {
if ! file $layername |grep -q ext ; then
	[ -f $layername ] && exitmsg "Unsupported file format" 2
	dd if=/dev/zero of="$layername" bs=1 count=1 seek=2G 2>&1 &&  \ 
	mkfs.ext3 -F -j "$layername" 2>&1 || exitmsg "Error create image file $layername" 3
	pfsload $layername
	else
	cat /proc/mounts | grep -q "$layername"  &&  exitmsg "$layername already mounted" 1
	pfsload -u $layername
fi
}

function mkwhitelist () {
	echo -e "/tmp/includedfiles\n/tmp/excludedfiles" > /tmp/excludedfiles
	if ! [ -f "$FILELIST" ] ;then
	echo "make /.savelist"
cat > "$FILELIST" <<EndOF
!/dev
!/proc
!/sys
!/run
!/memory
!/tmp
!/mnt
!/media
!/var/spool
#!/var/log
EndOF
	fi
	grep ^! "$FILELIST" | sed 's:!:\^:' > /tmp/savelist.black
	grep -v '^[!#]' "$FILELIST" && grep -v '^[!#]' "$FILELIST" >/tmp/savelist.white
	find ${changesDir} \( -type l -o -type f \) | sed 's|'${changesDir}'|/|' >/tmp/allfiles
	find ${changesDir}  -type d -empty | sed 's|'${changesDir}'|/|' >>/tmp/allfiles
	grep -q . /tmp/savelist.black && grep -f /tmp/savelist.black /tmp/allfiles >> /tmp/excludedfiles
	sed -i 's:^/:\^/:' /tmp/excludedfiles
	grep -vf /tmp/excludedfiles /tmp/allfiles > /tmp/includedfiles
	[ -f /tmp/savelist.white ] && grep -f /tmp/savelist.white /tmp/allfiles >> /tmp/includedfiles
	cat /tmp/includedfiles
}

function  sync2layer () {
	layermp=$(aufs-n 1)
	[ -d  $layermp -a -w $layermp ] || exitmsg "Layer mounted RO" 4
	filelist=$(mkwhitelist |sort |uniq )
	for file in $filelist ; do
	echo "$file" |grep -q .wh* && continue
	echo "$file" |grep -q  "$layermp" && continue
	[ -e $file ] || continue
	cp -uPR --parents ${file} ${layermp}/ || ( sync ; mount -o remount $layermp ; mount -o remount / ; exitmsg "Copy $file error" 2 )
		if [ -f $file ] ; then
			if lsof $file >/dev/null 2>&1; then
				[ $? = 0 ] && echo -ne "$file ${color_blue} -- is open now,  copied ${color_default}\n"
				continue
			fi 
		rm -f ${changesDir}${file}  &&	echo -ne "${file} -- ${color_green}moved ${color_default}\n"
		continue
		fi
		[ -d $file ] && echo -ne "$file ${color_yellow} -- is empty dir, created ${color_default}\n" && continue
		[ -L $file ] && echo -ne "$file  -- is link, created ${color_default}\n" && continue
		echo  -ne "$file ${color_red} -- uknown type, copied ${color_default}\n"
	done
	sync
	mount -o remount $layermp && mount -o remount /
}

[ "$1" = "-h" -o "$1" = "--help" ] && help

allow_only_root

if ! [ $1 ] ; then
sync2layer
exit
fi 

layername="$1"

if echo $layername |egrep -q "\.rom$" ; then
	filelayer || exitmsg "pfsload $layername ERROR" 5
else
	dirlayer || exitmsg "pfsload $layername ERROR" 6
fi 

sync2layer

exit