#!/bin/sh
# defrag v0.07 by Con Kolivas <kernel@kolivas.org
# Braindead fs-agnostic defrag to rewrite files in order largest to smallest
# Run this in the directory you want all the files and subdirectories to be
# reordered. It will only affect one partition.
# Are you really crazy enough to be using this? It might blow your data
# into tiny little useless chunks.
#
# модифицирован haku

ionice -c3 -p$$

trap 'abort' 1 2 15

renice 19 $$ > /dev/null

abort()
{
	echo -e "\nВыполнение прервано успешно"
	rm -f tmpfile dirlist
	exit 1
}

fail()
{
	echo -e "\nFailed! Проверьте целостность последнего файла"
	abort
}

declare -i filesize=0
declare -i numfiles=0
declare -i in_chunks=0
declare -i out_chunks=0

#The maximum size of a file we can easily cache in ram
declare -i maxsize=$((`awk '/MemTotal/ {print $2}' /proc/meminfo`*1024))
(( maxsize-= `awk '/Mapped/ {print $2}' /proc/meminfo` ))
(( maxsize/= 2))

if [[ -a tmpfile || -a dirlist  ]] ; then
	echo dirlist or tmpfile exists
	exit 1
fi

# Sort in the following order:
# 1) Depth of directory
# 2) Size of directory descending
# 3) Filesize descending
# I made this crap up. I'ts completely unvalidated.

echo -e "Создаю список файлов для обработки... \c"

#stupid script to find max directory depth
find -xdev -type d -printf "%d\n" | sort -n | uniq > dirlist

#sort directories in descending size order
cat dirlist | while read d;
do
	find -xdev -type d -mindepth $d -maxdepth $d -printf "\"%p\"\n" | \
		xargs du -bS --max-depth=0 | \
		sort -k 1,1nr -k 2 |\
		cut -f2 >> tmpfile
	if (( $? )) ; then
		fail
	fi

done

rm -f dirlist

#sort files in descending size order
cat tmpfile | while read d;
do
	find "$d" -xdev -type f -maxdepth 1 -printf "%s\t%p\n" | \
		sort -k 1,1nr | \
		cut -f2 >> dirlist
	if (( $? )) ; then
		fail
	fi
done

rm -f tmpfile

numfiles=`wc -l dirlist | awk '{print $1}'`

echo -e "готово, $numfiles файла(-ов) будут дефрагментированы"

#copy to temp file, check the file hasn't changed and then overwrite original
cat dirlist | while read i;
do
	(( --numfiles ))
	if [[ ! -f $i ]]; then
		continue
	fi

	#We could be this paranoid but it would slow it down 1000 times
	#if [[ `lsof -f -- "$i"` ]]; then
	#	echo -e "\n File $i open! Skipping"
	#	continue
	#fi

	filesize=`find "$i" -printf "%s"`
	# read the file first to cache it in ram if possible
	if (( filesize < maxsize ))
	then
		echo -e "\rещё $numfiles, (кэширую в озу)...\c"
		cat "$i" > /dev/null
	else
		echo -e "\rещё $numfiles, двигаю $filesize байт...\c"
	fi

	in_chunks=`filefrag "$i" | awk '{print $(NF - 2)}'`
	datestamp=`find "$i" -printf "%s"`
	if (( in_chunks != 1 )) 
	then
		cp -a -f "$i" tmpfile
		out_chunks=`filefrag "tmpfile" | awk '{print $(NF - 2)}'`
			if (( out_chunks < in_chunks ))
			then 
				# check the file hasn't been altered since we copied it
				if [[ `find "$i" -printf "%s"` != $datestamp ]] ; then
					echo -e " \e[1;41mисходный файл изменился, пропускаю\e[0m"
					continue
				fi
				echo -e " \e[1;36m($in_chunks-->$out_chunks) дефрагментирован $i\e[0m"
				mv -f tmpfile "$i"
			else 
				echo -e " \e[3;36m $out_chunks не лучше $in_chunks, пропускаю $i\e[0m"
				rm tmpfile
			fi
	else 
		echo -e " \e[1;34mфайл $i не фрагментирован, пропускаю\e[0m"
		continue
	fi

	if (( $? )) ; then
		fail
	fi
done

echo -e "\nЗавершено успешно"
rm -f dirlist