#!/bin/sh
# linux sphinx's disk carvulator
# part of the gnnix conspiracy

# usage dfree devicename amount-needed
dfree()
{
req=$2
str=`fdisk -l /dev/${1} | grep -E '^Disk'`
bytes=${str#*, }
max=${bytes% bytes}
typeset -i sum=0
fdisk -l /dev/${1} | grep /dev/ | grep -v Extended | grep -v Disk | sed 's/[*|+]//g' > /tmp/dfree
while read j
do
if [ ! -z "$j" ]; then
set $j
((sum=$4 +$sum))
fi
done < /tmp/dfree

echo "Results Of Disk Space Analysis
"
echo "     Max: $max" > /tmp/carve
((sum=($sum*1024)))
echo "  In use: $sum" >> /tmp/carve
((dif=$max -$sum))
echo "    free: $dif" >> /tmp/carve
# 4*1024*1024*1024 minimum
#if (( $dif > 4294967296 )); then
echo "required: $req" >> /tmp/carve
if (( $dif > $req )); then
echo "Status: Plenty Of Room" >> /tmp/carve
return 0
else
echo "
      * NOT ENOUGH FREE DISK SPACE *
         NO FORMATTING PERFORMED
Use cfdisk to free up $req bytes and retry
" >> /tmp/carve
return 1
fi
}

# usage: autocarve pattern devname as in autocarve 0 hda
autocarve()
{
rm -f /tmp/crvr.map
memsz=`grep MemTotal: /proc/meminfo |sed 's/ //g'`
str=${memsz#MemTotal:}
mem=${str%kB}
((pmem=$mem*1024))
# specify name:size_in_bytes - use 0 for ext size $pmem for swap - order is significant
PARTITMAP[0]="boot:10000000 slash:100000000 swap:${pmem} ext:0 var:300000000 usr:2000000000 tmp:500000000 local:500000000 home:500000000"
PARTITMAP[1]="boot:10000000 slash:100000000 swap:${pmem} ext:0 var:300000000 usr:2000000000 tmp:500000000 local:500000000 home:500000000"
PARTITMAP[2]="boot:10000000 slash:100000000 swap:${pmem} ext:0 var:300000000 usr:2000000000 tmp:500000000 local:500000000 home:500000000"

# determine total needed first pass
for i in ${PARTITMAP[${1}]}
do
 ((b=$b + ${i#*:}))
done
dfree $2 $b
if (($? == 1)); then
return 1
fi

str=`fdisk -l /dev/${2} | grep -E '^Disk'`
bytes=${str#*, }
max=${bytes% bytes}
str=`fdisk -l /dev/${2} | grep -E 'cylinders$'`
bytes=${str#*sectors/track, }
cylcnt=${bytes% cylinders}
((cylsz=${max}/${cylcnt}))

echo "Resulting Disk Map

name  cylinders  boot  type" >> /tmp/carve
echo "------------------------------" >> /tmp/carve
sum=0
for i in ${PARTITMAP[${1}]}
do
 ((c=${i#*:} /$cylsz))
 n=${i%:*}
 if [ "$n" = "slash" ]; then
  echo "$n     $c      *     linux" >> /tmp/carve
  echo ",${c},L,*" >> /tmp/crvr.map
 elif [ "$n" = "swap" ]; then
  echo "$n     $c            swap" >> /tmp/carve
  echo ",${c},S" >> /tmp/crvr.map
 elif [ $n = "ext" ]; then
  echo ",,E" >> /tmp/crvr.map
 else
  echo "$n     $c            linux" >> /tmp/carve
  echo ",${c},L" >> /tmp/crvr.map
 fi
 ((sum=${c} +$sum))
done

echo "
   total bytes: $max" >> /tmp/carve
echo "cylinder count: $cylcnt" >> /tmp/carve
echo " cylinder size: $cylsz" >> /tmp/carve
echo "     used cyls: $sum" >> /tmp/carve
((fcyl=$cylcnt-$sum))
echo "     free cyls: $fcyl" >> /tmp/carve
((tot=$max-($max-($sum*$cylsz))))
echo "    used bytes: $tot" >> /tmp/carve
((tot=$max-($max-($fcyl*$cylsz))))
echo "    free bytes: $tot 
" >> /tmp/carve
#sfdisk /dev/${2} << /tmp/crvr.map
#sfdisk -R /dev/${2}
}

# carve disk /dev/sda with pattern 1
autocarve 1 sda
cat /tmp/carve