find the file by sector in filesystem

sector2file.sh

#!/bin/bash

# sector_list sample as below:
# 0
# 512
# 4087578
# 4087579
# 6324224
# 
# You should build a sector_list firstly, and then execute this script to catch the files
# At the end of the task, it will tell you where the result is written to...

if [ $# -lt 2 ];then
	echo "usage:$0 dev sector_list"
	exit 1
fi

dev="$1"
sectorlist="$2"
outputfile="`date +%Y%m%d%H%M%S`.result"

# check the device
if [ ! -b "$dev" ]; then
	echo "invalid device"
	exit 1
fi

# check the file
if [ ! -f "$sectorlist" ];then
	echo "$sectorlist is not existed"
	exit 1
fi

# got the size of block
blksize=`debugfs -R 'stats' $dev | grep "Block size:" | awk '{print $3}'`
echo "blksize: $blksize"
sector_per_blk=`echo "$blksize / 512" | bc`
echo "sectors per block:$sector_per_blk"

tmp="$$.tmplog"
echo > $tmp
# scan the sectors in the list
while read line
do
    sector=$(echo $line | awk '{print $1}')
 	# calc block
	blk=`echo "$sector / $sector_per_blk" | bc`	
	#echo "$sector => $blk"
	# find inode by block
	inode=`debugfs -R "icheck $blk" $dev | grep -v debugfs | grep -v Inode | grep -v "not found" | awk '{print $2}'`
	if [ "$inode" == "" ];then
		#echo "blk $blk miss inode"
		continue
	fi
	# find the file by inode
	file=`debugfs -R "ncheck $inode" $dev | grep -v debugfs | grep -v Inode | awk '{print $2}'`
	echo $file >> $tmp
done < "$sectorlist"

echo "result write into $outputfile"
cat $tmp | sort -u > $outputfile

rm -f $tmp