#!/bin/bash

# mkinitrd
#
# Written by Erik Troan <ewt@redhat.com>
#
# Contributors:
#	Elliot Lee <sopwith@cuc.edu>
#	Miguel de Icaza <miguel@nuclecu.unam.mx>
#	Christian 'Dr. Disk' Hechelmann <drdisk@ds9.au.s.shuttle.de>
#	Michael K. Johnson <johnsonm@redhat.com>
#	Pierre Habraken <Pierre.Habraken@ujf-grenoble.fr>
#	Jakub Jelinek <jj@ultra.linux.cz>
#	Carlo Arenas Belon (carenas@chasqui.lared.net.pe>

PATH=/sbin:$PATH
export PATH

VERSION=2.4.1

compress=1
target=""
kernel=""
force=""
verbose=""
MODULES=""
img_vers=""
modulefile=/etc/conf.modules
IMAGESIZE=1500
PRESCSIMODS="scsi_mod sd_mod"
fstab="/etc/fstab"

usage () {
    echo "usage: `basename $0` [--version] [-v] [-f] [--ifneeded] [--preload <module>]" >&2
    echo "       [--omit-scsi-modules] [--omit-raid-modules] [--with=<module>]" >&2
    echo "       [--image-version] [--fstab=<fstab>] [--nocompress] <initrd-image>" >&2
    echo "       <kernel-version>" >&2
    echo "       (ex: `basename $0` /boot/initrd-2.2.5-15.img 2.2.5-15)" >&2
    exit 1
}

findmodule() {
    skiperrors=""
    modName=$2
    if [ $(echo $modName | cut -b1) = "-" ]; then
	skiperrors=1
	modName=$(echo $modName | cut -b2-)
    fi

    if [ "$modName" = "pluto" ]; then
	findmodule "" fc4
	findmodule "" soc
    fi
    if [ "$modName" = "fcal" ]; then
	findmodule "" fc4
	findmodule "" socal
    fi
    fmPath=$(cd /lib/modules/$kernel; find . -type f -name $modName.o|\
		perl -e '$_=<>; s/^..//; print;')

    if [ ! -f /lib/modules/$kernel/$fmPath ]; then
	if [ -n "$skiperrors" ]; then
	    return
	fi

        # ignore the absence of the scsi modules
	for n in $PRESCSIMODS; do
	    if [ "$n" = "$modName" ]; then
		return;
	    fi
	done;
    
	echo "No module $modName found for kernel $kernel" >&2
	exit 1
    fi

    # only need to add each module once
    if echo $MODULES | grep $fmPath >/dev/null 2>&1 ; then : ; else
	MODULES="$MODULES $fmPath"
    fi
}

inst() {
    if [ "$#" != "2" ];then
        echo "usage: inst <file> <destination>"
        return
    fi 
    [ -n "$verbose" ] && echo "$1 -> $2"
    cp $1 $2
}

while [ $# -gt 0 ]; do
    case $1 in
	--fstab*)
	    if echo $1 | grep '=' >/dev/null ; then
	    	fstab=`echo $1 | sed 's/^--with=//'`
	    else
		fstab=$2
		shift
	    fi		    
	    ;;

	--with*)
	    if echo $1 | grep '=' >/dev/null ; then
	    	modname=`echo $1 | sed 's/^--with=//'`
	    else
		modname=$2
		shift
	    fi		    

	    basicmodules="$basicmodules $modname"
	    ;;

	--version)
	    echo "mkinitrd: version $VERSION"
	    exit 0
	    ;;

	-v)
	    verbose=-v
	    ;;

	--nocompress)
	    compress=""
	    ;;

	--ifneeded)
	    ifneeded=1
	    ;;

	-f)
	    force=1
	    ;;
	--preload)
	    if echo $1 | grep '=' >/dev/null ; then
	    	modname=`echo $1 | sed 's/^--preload=//'`
	    else
		modname=$2
		shift
	    fi		    
	    PREMODS="$PREMODS $modname"
	    ;;
	--omit-scsi-modules)
	    PRESCSIMODS=""
	    noscsi=1;
	    ;;
	--omit-raid-modules)
	    noraid=1;
	    ;;
	--image-version)
	    img_vers=yes
	    ;;
	*)
	    if [ -z "$target" ]; then
		target=$1
	    elif [ -z "$kernel" ]; then
		kernel=$1
	    else
		usage
	    fi
	    ;;
    esac

    shift
done

if [ -z "$target" -o -z "$kernel" ]; then
    usage
fi

if [ -n "$img_vers" ]; then
    target="$target-$kernel"
fi

if [ -z "$force" -a -f $target ]; then
    echo "$target already exists." >&2
    exit 1
fi

if [ ! -d /lib/modules/$kernel ]; then
    echo "/lib/modules/$kernel is not a directory." >&2
    exit 1
fi

for n in $PREMODS; do
	findmodule "" $n
done

if [ -z "$noscsi" ]; then
    for n in $PRESCSIMODS; do
	    findmodule scsi $n
    done

    if [ ! -f $modulefile ]; then
        modulefile=/etc/modules.conf
    fi
    if [ -f $modulefile ]; then
	scsimodules=`grep scsi_hostadapter $modulefile | grep -v '^[ 	]*#' | LC_ALL=C sort -u | awk '{ print $3 }'`
	for n in $scsimodules; do
    # for now allow scsi modules to come from anywhere.  There are some
    # RAID controllers with drivers in block/
	    findmodule "" $n
	done
    fi
fi

if [ -z "$noraid" ]; then
    # load appropriate raid devices if necessary
    if grep '^/dev/md' $fstab | grep -v noauto >/dev/null 2>&1 ; then
	for number in $(grep '^[ 	]*raid-level' /etc/raidtab |
			  awk '{print $2}' | LC_ALL=C sort -u) ; do
	    case $number in
	    [0145])
		findmodule "" raid$number
		;;
	    *)
		echo "raid level $number (in /etc/raidtab) not recognized" >&2
		;;
	    esac
	done
    fi
fi

# check to see if we need to set up a loopback filesystem
rootdev=$(awk '{ if ($2 == "/") { print $1; }}' $fstab)
if echo $rootdev | cut -d/ -f3 | grep loop >/dev/null; then
    key="^# $(echo $rootdev | cut -d/ -f3 | tr '[a-z]' '[A-Z]'):"
    if ! grep "$key" $fstab > /dev/null; then
	echo "The root filesystem is on a $rootdev, but there is no magic entry in $fstab" 1>&2
	echo "for this device. Consult the mkinitrd man page for more information" 2>&2
	exit 1
    fi

    line=$(grep "$key" $fstab)
    loopDev=$(echo $line | awk '{print $3}')
    loopFs=$(echo $line | awk '{print $4}')
    loopFile=$(echo $line | awk '{print $5}')

    basicmodules="$basicmodules -loop"
    if [ "$loopFs" = "vfat" -o "$loopFs" = "msdos" ]; then
	basicmodules="$basicmodules -fat"
    fi
    basicmodules="$basicmodules -${loopFs}"
	
fi

for n in $basicmodules; do 
    findmodule "" $n
done

if [ -n "$ifneeded" -a -z "$MODULES" ]; then
    if [ -n "$verbose" ]; then
	echo "No modules are needed -- not building initrd image."
    fi
    exit 0
fi

if [ -n "$verbose" ]; then
    echo "Using modules: $MODULES"
fi

MNTIMAGE=/tmp/initrd.$$
IMAGE=/tmp/initrd.img-$$
MNTPOINT=/tmp/initrd.mnt-$$
RCFILE=$MNTIMAGE/linuxrc

if [ -f $MNTIMAGE ]; then
    echo "$MNTIMAGE already exists.  Remove it and try again" >&2
    exit 1
fi

if [ -f $IMAGE ]; then
    echo "$IMAGE already exists. Remove it and try again" >&2
    exit 1
fi

dd if=/dev/zero of=$IMAGE bs=1k count=$IMAGESIZE 2> /dev/null

for devnum in 0 1 2 3 4 5 6 7 8; do
    if losetup /dev/loop$devnum $IMAGE 2>/dev/null ; then break; fi
done

if [ "$devnum" = "8" ]; then
    rm -rf $MNTPOINT $IMAGE
    echo "All of your loopback devices are in use!" >&2
    exit 1
fi

LODEV=/dev/loop$devnum

# We have to "echo y |" so that it doesn't complain about $IMAGE not
# being a block device
echo y | mke2fs $LODEV $IMAGESIZE >/dev/null 2>/dev/null

if [ -n "$verbose" ]; then
    echo "Using loopback device $LODEV"
fi

mkdir -p $MNTPOINT
mount -t ext2 $LODEV $MNTPOINT || {
	echo "Can't get a loopback device"
	exit 1
}

mkdir -p $MNTIMAGE
mkdir -p $MNTIMAGE/lib
mkdir -p $MNTIMAGE/bin
mkdir -p $MNTIMAGE/etc
mkdir -p $MNTIMAGE/dev
mkdir -p $MNTIMAGE/loopfs

# We don't need this directory, so let's save space
rm -rf $MNTPOINT/lost+found

if [ -x "/bin/ash.static" ] ; then
	SHELLSRC=/bin/ash.static
	SHELLDST=/bin/ash
else
	SHELLSRC=/sbin/sash
	SHELLDST=/bin/sash
fi

inst $SHELLSRC "$MNTIMAGE$SHELLDST"
inst /sbin/insmod.static "$MNTIMAGE/bin/insmod"

for MODULE in $MODULES; do
    cp $verbose -a /lib/modules/$kernel/$MODULE $MNTIMAGE/lib
done

for n in console null ram systty tty[1234]; do
    cp -a /dev/$n $MNTIMAGE/dev
done

echo "#!$SHELLDST" > $RCFILE
echo "" >> $RCFILE
echo "aliasall" >> $RCFILE
echo "" >> $RCFILE

for MODULE in $MODULES; do
    module=`echo $MODULE | sed "s|.*/||" | sed "s/.o$//"`

    options=`sed -n -e "s/^options[ 	][ 	]*$module[ 	][ 	]*//p" $modulefile`

    if [ -n "$verbose" ]; then
        echo "Loading module $module with options $options"
    fi
    echo "echo \"Loading $module module\"" >> $RCFILE
    echo "insmod /lib/$module.o $options" >> $RCFILE
done

if [ -n "$loopDev" ]; then
    if [ ! -d /initrd ]; then
	mkdir /initrd
    fi

    cp -a $loopDev $MNTIMAGE/dev
    cp -a $rootdev $MNTIMAGE/dev
    echo "echo Mounting device containing loopback root filesystem" >> $RCFILE
    echo "mount -t $loopFs $loopDev /loopfs" >> $RCFILE
    echo "echo Setting up loopback device $rootdev" >> $RCFILE
    echo "losetup $rootdev /loopfs$loopFile" >> $RCFILE
fi

chmod +x $RCFILE

(cd $MNTIMAGE; tar cf - .) | (cd $MNTPOINT; tar xf -)

umount $MNTPOINT
losetup -d $LODEV

if [ -n "$compress" ]; then
    gzip -9 < $IMAGE > $target
else
    cp -a $IMAGE $target
fi
rm -rf $MNTIMAGE $MNTPOINT $IMAGE

