Subversion Repositories livecd

#!/bin/ash

#

# Original version from http://www.linux-live.org/

#

# modified by Urs Beyerle, PSI

# - to allow LiveCD mounted over NFS

# - add support for LiveCD on SATA devices

# - to allow LiveCD mounted over CIFS

export PATH=.:/:/usr/sbin:/usr/bin:/sbin:/bin

. liblinuxlive

echolog "mounting /proc and /sys filesystems"

mount -t proc proc /proc

mount -t sysfs sysfs /sys

ln -sf /proc/mounts /etc/mtab # this allows us to use umount -a

# setup DEBUGCMD variable. If debug boot option is present, call debug()

# function several times during script's execution

if [ "`cmdline_parameter debug`" ]; then DEBUGCMD="debug"; else DEBUGCMD=""; fi

$DEBUGCMD

# amount of RAM to store changes

RAMSIZE="`cmdline_value ramsize`"

if [ "$RAMSIZE" = "" ]; then RAMSIZE="70%"; fi

# I have to set these variables very carefully

UNION=/union

MEMORY=/memory

MOUNTDIR=livecd

CHANGES=$MEMORY/changes

COPY2RAM=$MEMORY/copy2ram

IMAGES=$MEMORY/images

INITRAMDISK=$MOUNTDIR/live

# set NFSROOT and NFSOPT 

NFSROOT="`cmdline_value nfsroot`"

NFSOPTS="`cmdline_value nfsopts`"

if [ "$NFSOPTS" = "" ]; then

    NFSOPTS=nolock,ro,rsize=8192,wsize=8192,hard,intr

fi

# set CIFSROOT and CIFSOPTS

CIFSROOT="`cmdline_value cifsroot`"

CIFSOPTS="`cmdline_value cifsopts`"

# we need cdrom support, isofs support, unionfs/aufs support, etc

modprobe_essential_modules

# disable DMA if nodma parameter is used

setup_dma

$DEBUGCMD

# if NFSROOT is set:

echolog "check for nfsroot or cifsroot"

if [ "$NFSROOT" != "" ]; then

   echolog "nfsroot: $NFSROOT"

   $DEBUGCMD

   load_network_modules

   $DEBUGCMD

   get_dhcp_lease

   $DEBUGCMD

   modprobe_nfs_modules

# if CIFSROOT is set

elif [ "$CIFSROOT" != "" ]; then

   echolog "cifsroot: $CIFSROOT"

   $DEBUGCMD

   load_network_modules

   $DEBUGCMD

   get_dhcp_lease

   $DEBUGCMD

   modprobe_cifs_modules

fi

$DEBUGCMD

# $UNION will be used as a root directory, livecd modules will be added soon.

echolog "setup union on $UNION"

mkdir -p $UNION

mkdir -p $MEMORY

CHANGESDEV="`cmdline_value changes`"

if [ "$CHANGESDEV" != "" ]; then

   echo "mounting $CHANGESDEV to $MEMORY"

   # we may need usb and sata support

   modprobe_usb_sata_modules

   mount_device $CHANGESDEV $MEMORY

else false; fi

# mount tmpfs only in the case when changes= boot parameter was empty

# or we were not able to mount the storage device

if [ $? -ne 0 ]; then mount -t tmpfs -o "size=$RAMSIZE" tmpfs $MEMORY; fi

mkdir -p $CHANGES

mkdir -p $COPY2RAM

mkdir -p $IMAGES

# mount unionfs or aufs

lsmod | grep -q ^unionfs

if [ $? -eq 0 ]; then  

    mount -t unionfs -o dirs=$CHANGES=rw unionfs $UNION

    if [ $? -ne 0 ]; then fatal "can't setup union in $UNION directory"; fi

    echolog "unionfs mounted"

else

    mount -t aufs -o br:$CHANGES=rw aufs $UNION

    if [ $? -ne 0 ]; then fatal "can't setup union (aufs) in $UNION directory"; fi

    echolog "aufs mounted"

fi

$DEBUGCMD

# try to find livecd data directory. If not found, try modprobing

# USB and SATA kernel modules and repeat the find procedure again

echolog "looking for data modules"

DATA="`find_live_data_dir $MOUNTDIR`";

if [ "$DATA" = "" ]; then modprobe_usb_sata_modules; DATA="`find_live_data_dir $MOUNTDIR`"; fi

if [ "$DATA" = "" ]; then fatal "Data for LiveCD not found."; fi

echolog "LiveCD found in: $DATA"

$DEBUGCMD

# If toram or copy2ram boot parameter is present, copy all .mo modules to RAM.

# (skip modules from /optional/ which are not listed in load= boot option)

# Finaly modify DATA variable so it will point to correct directory

if [ "`cmdline_parameter toram`" != "" -o "`cmdline_parameter copy2ram`" != "" ]; then

   echolog "copying modules to RAM, this may take some time"

   copy_to_ram $DATA $COPY2RAM

   cd_autoeject 1

   umount $DATA 2>/dev/null

   if [ $? -ne 0 ]; then umount `dirname $DATA` 2>/dev/null; fi

   DATA=$COPY2RAM

   cd_autoeject 0

fi

mkdir -p $UNION/boot

mount -o bind $DATA $UNION/boot

$DEBUGCMD

# DATA contains path to the base directory of all .mo images which need

# to be mounted and inserted into live filesystem. Do it now.

echolog "inserting all modules and creating live filesystem"

union_insert_modules $UNION $DATA $IMAGES

$DEBUGCMD

echo "copying rootchanges"

copy_rootchanges $DATA $UNION

$DEBUGCMD

echo "creating /etc/fstab"

activate_fstab $UNION

# More likely these directories aren't there.

# Even if they are, this won't hurt.

mkdir -p $UNION/proc

mkdir -p $UNION/sys

mkdir -p $UNION/tmp

chmod 1777 $UNION/tmp

mkdir -p $UNION/dev

mkdir -p $UNION/initrd

$DEBUGCMD

# no X? (set runlevel to 3)

if [ "`cmdline_parameter nox`" ]; then

  echo "set runlevel to 3"

  sed -i "s/id:.:initdefault:/id:3:initdefault:/" $UNION/etc/inittab

fi

$DEBUGCMD

# Union contains all the files and directories unioned from all modules.

# Change root directory to it, and move initrd's root to /livecd/live/initramdisk

# Finaly execute /sbin/init to start the distribution.

echolog "changing root directory..."

cd $UNION

mkdir -p $INITRAMDISK

umount /sys # we won't need it anymore

# if [ ! -e $UNION/dev/console ]; then mknod $UNION/dev/console c 5 1; fi

# Copy all dev files (found by mdev) to unioned dev directory

# so at least disk devices exist (your Linux may need them).

# Two exceptions, do not copy pty* and tty* devs.

if [ ! -e /dev/console ]; then mknod /dev/console c 5 1; fi

cp -fdR /dev . 2>/dev/null

if [ -x $UNION/usr/sbin/chroot ];

  then CHROOT=/usr/sbin/chroot

  else CHROOT=/usr/bin/chroot

fi

echolog "End of linux live scripts"

# pure magic ;-)

cat $UNION/bin/true >/dev/null

$DEBUGCMD

pivot_root . $INITRAMDISK

exec $CHROOT . sbin/init <dev/console >dev/console 2>&1

header "ERROR!"

echolog "You are not supposed to be here, something went wrong!"

echolog "Even Ctrl+Alt+Del won't help you in kernel panic."