#!/bin/sh

umask 026
PATH=$PATH:/sbin:/usr/sbin:/bin:/usr/bin

LOGDIR="/var/log/xfsdump"
DUMPDIR="/var/backup"	# An NFS mount would be a good idea
COMPRESS=gzip		# unset for none
COMPSUFF="gz"		# Suffix for compression program
LEVEL="9"		# default to incremental at level 9

while [ $# -ge 1 ]; do
    case $1 in
	-l )	LEVEL=$2
		shift ;;
	-v )	VERBOSE=1
		;;
	* )	echo "Usage: $0 [-l level]"
		exit 0 ;;
    esac
    shift
done

hostname=`hostname`
me=`which $0`
mybase=`basename $0`
mypath=`dirname $me`
[ -x $mypath/$mybase.local ] && $mypath/$mybase.local

croak() {
	test $VERBOSE && echo $1
}

dumppart() {
	partition=$1
	description=$2
	level=$3

	croak "Dumping $partition ($description) with level $level"

	# Set up logging
	logfile="${LOGDIR}/${description}.log"
	croak "logging to $logfile"
	mkdir -p `dirname $logfile` && touch $logfile

	if [ $level != 0 ]; then
	  hasfull=`xfsrestore -I level=0,mnt="$hostname:$partition" | sed 's/\s//g' | awk -F: '($1 == "pathname") {print $2}'`

	  if [ -z "$hasfull" ]; then
	    echo "$mybase: Level 0 inventory for $partition not found" | tee -a $logfile
	    echo "$mybase: Switching to level 0 (full backup)" | tee -a $logfile
	    level=0
	  fi
	fi

	# Calculate file name to use
	dumpfile="${DUMPDIR}/$hostname/${description}_level${level}.xfsdump"
	croak "Dumping $partition to $dumpfile"
	mkdir -p `dirname $dumpfile`

	# Mount if necessary
	mounted=`mount $partition 2>&1 | grep already`

	partname=`df $partition | tail -n 1 | awk '{print $1}'`
	longdesc="$description-level-$level"

	# Clean up inventory
	xfsinvutil >/dev/null 2>&1 -n -M ${hostname}:$partition -m "$longdesc" 01/01/2020

	# Remove old backup files
	if [ -f "$dumpfile" ]; then
	    croak "Removing old dump file $dumpfile"
	    rm -f "$dumpfile"
	fi

	if [ $VERBOSE ]; then
	    verbosity="-p30 -v verbose"
	else
	    verbosity="-v silent"
        fi

	# Just in case
	sync

	###
	# The actual dump happens here
	#
	xfsdump 2>>$logfile $verbosity -E -F -e -L "$partname" -M "$longdesc" -l $level -f $dumpfile $partition
	#
	###

	[ -z "$mounted" ] && umount $partition

	if [ ! -z $COMPRESS ] && [ -f "$dumpfile" ]; then
	    if [ ! -z $COMPSUFF ] && [ -f "$dumpfile.$COMPSUFF" ]; then
		croak "Removing old compressed dump file $dumpfile.$COMPSUFF"
		rm -f "$dumpfile.$COMPSUFF"
	    fi

	    # Calculate compression level, values -0 to -9 valid
	    complevel=-$(expr $level + 1)
	    if [ $complevel -lt -9 ]; then
		complevel="-9"
	    fi
	    if [ $complevel -gt 0 ]; then
		complevel="0"
	    fi

	    croak "Compressing $dumpfile with $COMPRESS $complevel"
	    $COMPRESS $complevel "$dumpfile"
	fi

	# All done for this partition
	croak "Dump $longdesc completed"
}

# Run xfsdump inventory consistency check
xfsinvutil -FC >/dev/null

vols=`grep -v '^#' /etc/fstab | grep -v '^$' |\
awk '($3 == "xfs" && $5 != 0) {print "dumppart",$2,$1,"$LEVEL;"}' |\
sed 's/LABEL=//'`

eval $vols

exit 0