rocklinux/scripts/Create-UMLRootfs

#!/bin/bash

#
# Commands in isofs.txt files:
#
# EVERY		from	to		Put this on every disk
# DISK1		from	to		Put this on the 1st disk
# SINGLE	from	to		Put it on any disk
# SPLIT		from	to		You may split it up over many disks
#
# BOOT		boot-options		Add this mkisofs options for 1st disk
#
# If you want to add multiple 'BOOT' lines, use the tag-name 'BOOTx' for
# the 2nd and all further lines.
#
# SCRIPT	script-name	args	Run given script for each image
#
# Intended for image post-processing. The first attached argument is the CD
# number and the second the image file.
#
cleanup () {
	# Cleanup used for EXIT
	umount $mountpoint
	rmdir -p $mountpoint
	losetup -d $loopdevice
}

eval `grep rockver scripts/parse-config`

if [ $# -eq 0 ] ; then
	echo
	echo "Usage: $0 [ -size MB ] [ -mkdebug ] [-prefix FS-Prefix] [-fs filesystem] Config"
	echo
	echo "E.g.: $0  -prefix my myconfig"
	echo "this will leave you with a file 'my_linux' (the kernel) and a file"
	echo "'my_rootfs' (the file system). Just start it with ./linux"
	echo
	exit 1
fi

src=0; mkdebug=0; fssize=0; full=0;
filesystem="reiserfs"

while true ; do
	case "$1" in
		-size)
			fssize=$2 ; shift ; shift ;;
		-mkdebug)
			mkdebug=1 ; shift ;;
		-fs)
			filesystem=$2; shift; shift ;;
		-prefix)
		 	 ufsprefix=$2; shift; shift ;;
		-full)
			 full=1; shift ;;
		-* | '')
			$0 ; exit 1 ;;
		*)
			cfg=$1 ; shift ; break ;;
	esac
done

if [ ! "x$ufsprefix" = "x" ]; then fsprefix=${ufsprefix}_; else fsprefix=""; fi
if [ -f ${fsprefix}rootfs -o -f ${fsprefix}linux ]; then
	echo "Sorry, there exists a file with the same name, please make sure"
	echo "that no ${fsprefix}linux and no ${fsprefix}rootfs exist here."
	exit 1
fi

# get the build id
if [ ! -d config/$cfg ]; then
	echo "I cannot find the selected Config '$cfg'!"
	exit 1
fi
buildid="`grep '^export ROCKCFG_ID=' config/$cfg/config | cut -f2 -d\'`"
if [ ! -d build/$buildid ]; then 
	echo "I cannot find the build for the Config '$cfg' (build/$buildid)"
	exit 1; 
fi

# check if there is  a kernel executable 
if [ ! -f build/$buildid/boot/linux -o "x" = "x$(grep UMLPATCH=\'1\' config/$cfg/config)" ]; then
	echo "I cannot find the executable kernel, "
	echo "or it seems that the UML Patch was not applied to the kernel."
	exit 1;
fi

# calculate the default disk size as all packages of that config + 1/3 of the same
if [ $fssize = 0 ]; then
	echo "Calculating optimal image size, may take some time ..."
	cfssize=$(cd build/$buildid; du -sm --exclude ROCK | awk '{print $1;}';cd $OLDPWD)
	echo "All packages consume $cfssize MB"
	freespace=$(( $cfssize / 3 ))
	fssize=$(( $cfssize + $freespace ))
	echo "Therefore I propose a fs size of $fssize, that leaves you $freespace MB of free space."
fi

# check if there is enough disk space
hereiskbfree=$(df -P $PWD | tail -n 1 | awk '{ print $4; }')
hereismbfree=$(( $hereiskbfree / 1024 ))
if [ $hereismbfree -lt $fssize ]; then
	echo "Sorry, you have only $hereismbfree MB free here, "
	echo "that is not enough for a rootfs of $fssize MB."
	exit 1
fi

# create the empty rootfs file
dd if=/dev/zero of=${fsprefix}rootfs seek=${fssize} count=1 bs=1M 

trap 'cleanup' EXIT

# find a free loop device
for i in `ls /dev/loop/*`; do 
	echo $i
	losetup $i ${fsprefix}rootfs
	if [ $? = 0 ]; then
		loopdevice=$i
		break
	fi
done

# make a filesystem
yes | mkfs -t $filesystem $loopdevice 

# loop-mount the file
mountpoint=${fsprefix}rootfs_mnt
mkdir -p $mountpoint
mount -t $filesystem $loopdevice $mountpoint

# install all
echo "Installing files, may take some time..."
if [ $full = 1 ]; then
	for i in build/$buildid/*; do 
		if [ $i = "build/$buildid/ROCK" ]; then continue; fi
		cp -rp $i $mountpoint
	done
fi


# Copy the executable kernel
cp $mountpoint/boot/linux ${fsprefix}linux