#! /bin/bash

set -e
usage=\
"Usage: `basename $0` blocks inodes rootdir target
Example: $0 1024 600 root rootimg"

function usage()
{
    if [ "$1" != "" ]; then
	echo "$1" 2>&1
    fi
    echo "$usage" 2>&1
    echo -n "" 2>&1
    exit 10
}

function INThandler()
{
    if [ "$0" = "INT" ]; then
	echo -n "Interrupt! " 2>&1
    fi
    if [ -n "$tmpfile" ] && [ -e "$tmpfile" ]; then	
	df $tmpfile 2>&1 > /dev/null && {
	    # echo -n "Unmounting ${tmpfile}. " 2>&1 ;
	    umount $tmpfile ;
	}

	echo -n "Removing ${tmpfile}. " 2>&1 ;
	rm $tmpfile
	
	[ -n "$tmpmount" ] && [ -d "$tmpmount" ] && {
	    echo -n "Removing $tmpmount." 2>&1 ;
	    rmdir $tmpmount ;
	}
    fi
    echo "" 2>&1
    exit 0
}

function make_nodes {
    local devicedir=$1
    local do_rm

    if [ "$devicedir" = "" ]; then
	echo -e "Emptry dedicedir. Cannot continue\a" 1>&2
	exit 10
    fi

    pushd "$devicedir" > /dev/null || { \
	echo -e "Cannot change to the directory $devicedir\a" 1>&2; 
	exit 10;
    }

    if [ `pwd` = "/dev" ]; then
	echo -e "Aieee! We are in device directory."\
		"Something is terribly wrong!\a" 1>&2
	exit 10
    fi

    echo "$devicedir" | grep "/dev$"  >/dev/null;
    if [ "$?" -ne "0" ]; then
	echo -e "Illegal devicedir $devicedir\a" 1>&2
	exit 10
    fi

    do_rm=no
    for node in $dir/* ; do
	if [ "$node" != "$dir"'/*' ]; then
	    if [ -b "$node" -o -c "$node" -o -l "$node" ]; then
		do_rm=yes
	    else
		echo -e "File $node not a node or link in directory $dir."\
		    "Refusing to continure.\a" 1>&2
		exit 10
	    fi
	fi
    done

    if [ "$do_rm" = "yes" ]; then
	rm $dir/*
    fi
             
    mknod console         c   5   1 
    mknod full	      c   1   7 
#    mknod hda	      b   3   0 
#    mknod hdb	      b   3  64 
#    mknod hdc	      b  22   0 
#    mknod hdd	      b  22  64 
    mknod kmem	      c   1   2 
    mknod mem	      c   1   1 
    mknod mtd0	      c  90   0 
    mknod mtd1	      c  90   2 
    mknod mtd2	      c  90   4 
    mknod mtd3	      c  90   6 
    mknod mtd4	      c  90   8 
    mknod mtd5	      c  90  10 
    mknod mtd6	      c  90  12 
    mknod mtd7	      c  90  14 
    mknod mtd8	      c  90  16 
    mknod mtd9	      c  90  18 
#    mknod mtd10	      c  90  20 
#    mknod mtd11	      c  90  22 
#    mknod mtd12	      c  90  24 
#    mknod mtd13	      c  90  26 
#    mknod mtd14	      c  90  28 
#    mknod mtd15	      c  90  30 
#    mknod mtd16	      c  90  32 
    mknod mtdblock0       b  31   0 
    mknod mtdblock1       b  31   1 
    mknod mtdblock2       b  31   2 
    mknod mtdblock3       b  31   3 
    mknod mtdblock4       b  31   4 
    mknod mtdblock5       b  31   5 
    mknod mtdblock6       b  31   6 
    mknod mtdblock7       b  31   7 
    mknod mtdblock8       b  31   8 
    mknod mtdblock9       b  31   9 
#    mknod mtdblock10      b  31  10 
#    mknod mtdblock11      b  31  11 
#    mknod mtdblock12      b  31  12 
#    mknod mtdblock13      b  31  13 
#    mknod mtdblock14      b  31  14 
#    mknod mtdblock15      b  31  15 
#    mknod mtdblock16      b  31  16 
    mknod mtdr0	      c  90   1 
    mknod mtdr1	      c  90   3 
    mknod mtdr2	      c  90   5 
    mknod mtdr3	      c  90   7 
    mknod mtdr4	      c  90   9 
    mknod mtdr5	      c  90  11 
    mknod mtdr6	      c  90  13 
    mknod mtdr7	      c  90  15 
    mknod mtdr8	      c  90  17 
    mknod mtdr9	      c  90  19 
#    mknod mtdr10          c  90  21 
#    mknod mtdr11          c  90  23 
#    mknod mtdr12          c  90  25 
#    mknod mtdr13          c  90  27 
#    mknod mtdr14          c  90  29 
#    mknod mtdr15          c  90  31 
#    mknod mtdr16          c  90  33 
    mknod null	      c   1   3 
    mknod port	      c   1   4
    mknod ppp             c 108   0   
    mknod ram0	      b   1   0 
    mknod ram1	      b   1   1 
    ln -s ram0 ram
    mknod random          c   1   8 
    mknod tty	      c   5   0 
    mknod tty0	      c   4   0 
    mknod tty1	      c   4   1 
#    mknod tty2	      c   4   2 
#    mknod tty3	      c   4   3 
#    mknod tty4	      c   4   4 
    mknod ttyAM0      c 204  16
    ln -s ttyAM0 ttyS0
    mknod urandom         c   1   9 
    mknod vcs0	      c   7   0 
    mknod vcs1	      c   7   1 
    mknod vcsa0	      c   7 128 
    mknod vcsa1	      c   7 129 
    mknod zero	      c   1   5

    popd >/dev/null;

}
       
id=`whoami`
[ "$id" != "root" ] && { \
  echo -e "You must be root to run \"$0 $*\"\a" 1>&2; \
  exit 10; \
}

realid=`who am i | perl -lne 'print $1 if(/!(\S+)/)'`

[ "$#" -lt 4 ] && usage

size=$1
inodes=$2
dir=$3
realtarget=$4

[ "$inodes" -gt 1 ] || usage "Inodes count \"$inodes\" too small"

[ -d "$dir" ] || usage "Cannot find directory $dir"

for subdir in bin sbin etc dev; do
    [ -d "$dir/$subdir" ] || \
    usage "Cannot find directory $subdir in $dir"
done


pid=$$

trap INThandler INT EXIT

tmpfile=/tmp/tmp.minix.$$
tmpmount=/tmp/tmp.mount.$$

if [ "${realtarget}X" = "X" ]; then 
    if [ "$realid" != "" ]; then
	target=/tmp/root_fs_$realid
    else
	target=/tmp/root_fs
    fi
else
    target=$realtarget
fi

[ -e $tmpfile ] && usage "Cannot create $tmpfile: file exists"

touch $tmpfile || {
    echo "Cannot create $tmpfile"
    test -e $tmpfile
    rm $tmpfile 2>&1 >/dev/null
    exit 10
}

dd if=/dev/zero of=$tmpfile bs=1k count=$size 2> /dev/null

mkdir $tmpmount || {
    echo "Cannot create $tmpmount"
    rm -f $tmpfile
    exit 10
}

echo "Creating minix filesystem"
/sbin/mkfs.minix -i $inodes $tmpfile

mount $tmpfile $tmpmount -o loop
cp -a $dir/* $tmpmount || {
    echo "Cannot copy files to $tmpmount"
    exit 10;
}

make_nodes $tmpmount/dev

chown -R root:root $tmpmount

echo "Blocks:"
df $tmpmount
echo ""

echo "Inodes:"
df -i $tmpmount
echo ""

echo "Filesystem root directory:"
ls $tmpmount

chown -R root:root $tmpmount

echo "Press enter to unmount and copy ramdisk image to $target"
read line

umount $tmpmount
if [ "$error" != "yes" ]; then
    if [ "${realidX}" != "X" -a "${realtarget}X" != "X" ]; then 
	sudo -u $realid test -f $target && sudo -u $realid rm -f $target
	sudo -u $realid cp $tmpfile $target
	sudo -u $realid ls -l $target
    else
	test -f $target && rm -f $target
	cp $tmpfile $target 
	chmod 666 $target
	ls -l $target
    fi
#    perl -e '$size='$size'*1024;
#             print sprintf("initrd_start=0x%08x initrd_end=0xc0800000\n" . 
#                           "Lauterbach root load address: 0x%08x\n",
#                           0xc0800000 - $size, 0x10800000 - $size);'
fi
rm $tmpfile
rm -r $tmpmount

found=no
for file in /tmp/tmp.mount.* /tmp/tmp.minix.*; do
    if [ -e $file ]; then
	if [ "$found" = "no" ]; then
	    echo -e "\n\n\aOld tmp files found, please clean them up."
	    found=yes
	fi
	ls -ld $file
    fi
done