Adding casper 1.77+debian-1.
[live-boot-grml.git] / scripts / casper
index 3d8c453..3a5e0ca 100644 (file)
 
 export PATH=/root/usr/bin:/root/usr/sbin:/root/bin:/root/sbin:/usr/bin:/usr/sbin:/bin:/sbin
 
-mountpoint=/cdrom
+mountpoint=/live_media
 
-mkdir -p $mountpoint
+root_persistence="casper-rw"
+home_persistence="home-rw"
+root_snapshot="casper-sn"
+home_snapshot="home-sn"
 
-overlay_method=unionfs
-if [ "${DPKG_ARCH}" = "ia64" ] || [ "${DPKG_ARCH}" = "hppa" ] || [ "${DPKG_ARCH}" = "sparc" ]; then
-    overlay_method=devmapper
-fi
+USERNAME="casper"
+USERFULLNAME="Live session user"
+HOST="live"
+BUILD_SYSTEM="Debian"
 
-USERNAME=ubuntu
-USERFULLNAME="Ubuntu LiveCD user"
-HOST=ubuntu
+mkdir -p $mountpoint
 
 [ -f /etc/casper.conf ] && . /etc/casper.conf
 
-export USERNAME USERFULLNAME HOST
+export USERNAME USERFULLNAME HOST BUILD_SYSTEM
+
+if [ "${BUILD_SYSTEM}" == "Ubuntu" ]; then
+    MP_QUIET="-Q"
+else
+    MP_QUIET="-q"
+fi
+
+parse_cmdline ()
+{
+    # looking for casper specifics options as kernel parameters
+    for x in $(cat /proc/cmdline); do
+        case $x in
+            userfullname=*)
+                export USERFULLNAME=${x#userfullname=}
+                export CASPERCONF="changed"
+                ;;
+            host=*)
+                export HOST=${x#host=}
+                export CASPERCONF="changed"
+                ;;
+            username=*)
+                export USERNAME=${x#username=}
+                export CASPERCONF="changed"
+                ;;
+            netboot*)
+                export NETBOOT=${x#netboot=} ;;
+            toram)
+                export TORAM=1 ;;
+            todisk=)
+                export TODISK=${x#todisk=} ;;
+            showmounts)
+                export SHOWMOUNTS=1 ;;
+            persistent)
+                export PERSISTENT=1 ;;
+            ip*)
+                STATICIP=${x#ip=}
+                if [ "${STATICIP}" == "" ]; then
+                    STATICIP="frommedia"
+                fi
+                export STATICIP ;;
+            casper-getty)
+                export CASPERGETTY=1 ;;
+            console=*)
+                export DEFCONSOLE=$(sed -e 's%.*console=%console=%' /proc/cmdline) ;;
+            bootfrom=*)
+                export LIVEMEDIA=${x#bootfrom=} ;;
+            live-media=*)
+                export LIVEMEDIA=${x#live-media=} ;;
+            debian-installer/locale=*)
+                export LOCALE=${x#debian-installer/locale=} ;;
+            locale=*)
+                export LOCALE=${x#locale=} ;;
+            kbd-chooser/method=*)
+                export KBD=${x#kbd-chooser/method=} ;;
+            keyb=*)
+                export KBD=${x#kbd=} ;;
+            console-setup/layoutcode=*)
+                export CSLAYOUT=${x#console-setup/layoutcode=} ;;
+            console-setup/variantcode=*)
+                export CSVARIANT=${x#console-setup/variantcode=} ;;
+            console-setup/modelcode=*)
+                export CSMODEL=${x#console-setup/modelcode=} ;;
+        esac
+    done
+
+    # sort of compatibility with netboot.h from linux docs
+    if [ -z "${NETBOOT}" ]; then
+        if [ "${ROOT}" == "/dev/nfs" ]; then
+            NETBOOT="nfs"
+            export NETBOOT
+        elif [ "${ROOT}" == "/dev/cifs" ]; then
+            NETBOOT="cifs"
+            export NETBOOT
+        fi
+    fi
+}
 
-casper_path() {
+is_casper_path() {
     path=$1
-    if [ -e "$path/casper/filesystem.cloop" ]; then
-        echo "$path/casper/filesystem.cloop"
-        return 0
-    elif [ -e "$path/casper/filesystem.squashfs" ]; then
-        echo "$path/casper/filesystem.squashfs"
-        return 0
+    if [ -d "$path/casper" ]; then
+        if [ "$(echo $path/casper/*.cloop)" != "$path/casper/*.cloop" ] ||
+            [ "$(echo $path/casper/*.squashfs)" != "$path/casper/*.squashfs" ] ||
+            [ "$(echo $path/casper/*.ext2)" != "$path/casper/*.ext2" ] ||
+            [ "$(echo $path/casper/*.dir)" != "$path/casper/*.dir" ]; then
+            return 0
+        fi
     fi
     return 1
 }
@@ -45,27 +123,45 @@ subdevices() {
 }
 
 get_backing_device() {
-       case "$1" in
-            *.cloop)
-                echo $(setup_loop "$1" "cloop" "/sys/block/cloop*")
-                       ;;
-            *.squashfs)
-                echo $(setup_loop "$1" "loop" "/sys/block/loop*")
-                ;;
-            *)
-                panic "Unrecognized casper filesystem: $1"
-                ;;
-       esac
+    case "$1" in
+        *.cloop)
+            echo $(setup_loop "$1" "cloop" "/sys/block/cloop*")
+            ;;
+        *.squashfs|*.ext2)
+            echo $(setup_loop "$1" "loop" "/sys/block/loop*")
+            ;;
+        *.dir)
+            echo "directory"
+            ;;
+        *)
+            panic "Unrecognized casper filesystem: $1"
+            ;;
+    esac
 }
 
-setup_cow() {
-       case "$1" in
-            unionfs)
-                setup_unionfs "$2" "$rootmnt"
-                ;;
-            devmapper)
-                setup_devmapper "$2" "$rootmnt"
-       esac
+match_files_in_dir() {
+    # Does any files match pattern $1 ?
+
+    local pattern="$1"
+    if [ "$(echo $pattern)" != "$pattern" ]; then
+        return 0
+    fi
+    return 1
+}
+
+mount_images_in_directory() {
+    directory="$1"
+    rootmnt="$2"
+    if match_files_in_dir "$directory/casper/*.cloop"; then
+        # Let's hope there's just one matching *.cloop... FIXME
+        setup_devmapper $(get_backing_device "$directory/casper/*.cloop") "$rootmnt"
+    elif match_files_in_dir "$directory/casper/*.squashfs" || 
+        match_files_in_dir "$directory/casper/*.ext2" ||
+        match_files_in_dir "$directory/casper/*.dir"; then
+        setup_unionfs "$directory/casper" "$rootmnt"
+    else
+        :
+    fi
 }
 
 sys2dev() {
@@ -78,9 +174,9 @@ setup_loop() {
     local module=$2
     local pattern=$3
 
-    modprobe -Qb "$module"
-    udevplug -W
+    modprobe "${MP_QUIET}" -b "$module"
+    udevsettle
+
     for loopdev in $pattern; do
         if [ "$(cat $loopdev/size)" -eq 0 ]; then
             dev=$(sys2dev "${loopdev}")
@@ -107,7 +203,7 @@ setup_devmapper() {
     backdev="$1"
     rootmnt="$2"
 
-    modprobe -Qb dm-mod
+    modprobe "${MP_QUIET}" -b dm-mod
     COW_DEVICE=/dev/ram1
     COW_NAME="casper-cow"
 
@@ -133,6 +229,26 @@ setup_devmapper() {
     mount -t $(get_fstype "$backdev") /dev/mapper/casper-backing "$rootmnt/rofs"
 }
 
+is_nice_device() {
+    sysfs_path="${1#/sys}"
+    if /lib/udev/path_id "${sysfs_path}" | grep -E -q "ID_PATH=(usb|pci-[^-]*-[ide|scsi|usb])"; then
+        return 0
+    fi
+    return 1
+}
+
+is_supported_fs ()
+{
+    # FIXME: do something better like the scan of supported filesystems
+    fstype="${1}"
+    case ${fstype} in
+        vfat|iso9660|udf|ext2|ext3|ntfs)
+            return 0
+            ;;
+    esac
+    return 1
+}
+
 where_is_mounted() {
     device=$1
     if grep -q "^$device " /proc/mounts; then
@@ -143,121 +259,427 @@ where_is_mounted() {
     return 1
 }
 
+used_fs_size ()
+{
+    # Returns used fs kbytes + 5% more
+    # You could pass a block device as $1 or the mount point as $2
+
+    dev="${1}"
+    mountp="${2}"
+
+    if [ -z "${mountp}" ]; then
+        mountp=$(where_is_mounted "${dev}")
+        if [ "$?" -gt 0 ]; then
+            mountp=/mnt/tmp_fs_size
+            mkdir -p "${mountp}"
+            mount -t $(get_fstype "${dev}") -o ro "${dev}" "${mountp}"
+            doumount=1
+        fi
+    fi
+
+    size=$(du -ks ${mountp} | cut -f1)
+    size=$(expr ${size} + ${size}/20 ) # FIXME: 5% more to be sure
+    needed_space=$(expr ${size} * 1024)
+
+    if [ ! -z "${doumount}" ]; then
+        umount "${mountp}"
+        rmdir "${mountp}"
+    fi
+    echo "${needed_space}"
+}
+
+copy_live_to() {
+    copyfrom="${1}"
+    copytodev="${2}"
+    copyto="${copyfrom}_swap"
+
+    size=$(used_fs_size "null" "${copyfrom}")
+
+    if [ "${copytodev}" = "ram" ]; then
+        # copying to ram:
+        freespace=$( expr $(awk '/MemFree/{print $2}' /proc/meminfo) + $( cat /proc/meminfo | grep Cached | head -n 1 | awk '/Cached/{print $2}' - ) )
+        mount_options="-o size=${size}k"
+        free_string="memory"
+        fstype="tmpfs"
+        dev="/dev/shm"
+    else
+        # it should be a writable block device
+        if [ -b "${copytodev}" ]; then
+            free_string="space"
+            freespace="$(df -k ${copytodev} | grep -s ${copytodev} | awk '{print $4}')"
+            fstype="$(get_fstype ${devname})"
+            dev="${copytodev}"
+        else
+            return 1
+        fi
+    fi
+    if [ ! ${freespace} -lt ${size}  ] ; then
+        [ "$quiet" != "y" ] && log_begin_msg "Not enough free ${free_string} to copy live media in ${copytodev}."
+        [ "$quiet" != "y" ] && log_end_msg
+        return 1
+    fi
+
+    # begin copying..
+    [ "$quiet" != "y" ] && log_begin_msg "Copying live media to ${copytodev}..." 
+    mkdir "${copyto}"
+    mount -t "${fstype}" ${mount_options} "${dev}" "${copyto}"
+    cp -a ${copyfrom}/* ${copyto} # "cp -a" from busybox also copies hidden files
+    umount ${copyfrom}
+    mount -r -o move ${copyto} ${copyfrom}
+    rmdir ${copyto}
+    [ "$quiet" != "y" ] && log_end_msg
+    return 0
+}
+
+try_mount ()
+{
+    dev="${1}"
+    mountp="${2}"
+    opts="${3}"
+
+    if where_is_mounted ${dev} > /dev/null; then
+        mount -o remount,"${opts}" ${dev} $(where_is_mounted ${dev}) || panic "Remounting failed"
+        mount -o bind $(where_is_mounted ${dev}) ${mountp} || panic "Cannot bind-mount"
+    else
+        mount -t $(get_fstype "${dev}") -o "${opts}" "${dev}" "${mountp}" || panic "Cannot mount ${dev} on ${mountp}"
+    fi
+}
+
 find_cow_device() {
+    pers_label="${1}"
+    cow_backing="/${pers_label}-backing"
     for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop); do
         for dev in $(subdevices "${sysblock}"); do
             devname=$(sys2dev "${dev}")
-            if [ "$(/lib/udev/vol_id -l $devname 2>/dev/null)" = "casper-rw" ]; then
+            if [ "$(/lib/udev/vol_id -l $devname 2>/dev/null)" = "${pers_label}" ]; then
                 echo "$devname"
                 return
-            elif [ "$(get_fstype ${devname})" = "vfat" ]; then
-                mkdir -p /cow-backing
-                if where_is_mounted ${devname} > /dev/null; then
-                    mount -o remount,rw ${devname} $(where_is_mounted ${devname}) || panic "Remounting failed"
-                    mount -o bind $(where_is_mounted ${devname}) /cow-backing || panic "Cannot bind-mount"
-                else
-                    mount -t $(get_fstype "${devname}") -o rw "${devname}" /cow-backing || panic "Cannot mount $devname on /cow-backing"
-                fi
-
-                if [ -e "/cow-backing/casper-rw" ]; then
-                    echo $(setup_loop "/cow-backing/casper-rw" "loop" "/sys/block/loop*")
+            elif [ "$(get_fstype ${devname})" = "vfat" ]; then # FIXME: all supported block devices should be scanned
+                mkdir -p "${cow_backing}"
+                try_mount "${devname}" "${cow_backing}" "rw"
+                if [ -e "${cow_backing}/${pers_label}" ]; then
+                    echo $(setup_loop "${cow_backing}/${pers_label}" "loop" "/sys/block/loop*")
                     return 0
                 else
-                    umount /cow-backing
+                    umount ${cow_backing}
                 fi
             fi
-            
         done
     done
-    return 1    
 }
 
-setup_unionfs() {
-       backdev="$1"
-       rootmnt="$2"
-        modprobe -Qb unionfs
-        mkdir -p /cow
-
-        if grep -q persistent /proc/cmdline; then
-            i=0
-            # We love udev and the kernel!
-            while [ "$i" -lt 300 ]; do
-                cowdevice=$(find_cow_device) 
-                if [ -b "$cowdevice" ]; then
-                    mount -t $(get_fstype "$cowdevice") -o rw "$cowdevice" /cow || panic "Can not mount $cowdevice on /cow"
-                    break
-                fi
-                sleep 5
-#                sleep 0.1
-                i=$(( $i + 1 ))
-            done
+find_files()
+# return the first of $filenames found on vfat and ext2 devices
+# FIXME: merge with above function
+{
+    filenames="${1}"
+    snap_backing="/snap-backing"
+    for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop); do
+        for dev in $(subdevices "${sysblock}"); do
+            devname=$(sys2dev "${dev}")
+            devfstype="$(get_fstype ${devname})"
+            if [ "${devfstype}" = "vfat" ] ||  [ "${devfstype}" = "ext2" ] ; then # FIXME: all supported block devices should be scanned
+                mkdir -p "${snap_backing}"
+                try_mount "${devname}" "${snap_backing}" "ro"
+                for filename in ${filenames}; do
+                    if [ -e "${snap_backing}/${filename}" ]; then
+                        echo "${devname} ${snap_backing} ${filename}"
+                        return 0
+                    fi
+                done
+                umount ${snap_backing}
+            fi
+        done
+    done
+}
+
+do_netmount() {
+    rc=1
+
+    modprobe "${MP_QUIET}" af_packet # For DHCP
+
+    ipconfig ${DEVICE} /tmp/net-${DEVICE}.conf
+
+    if [ "${NFSROOT}" = "auto" ]; then
+        NFSROOT=${ROOTSERVER}:${ROOTPATH}
+    fi
+
+    [ "$quiet" != "y" ] && log_begin_msg "Trying netboot from ${NFSROOT}"
+
+    if [ "${NETBOOT}" != "nfs" ] && do_cifsmount ; then
+        rc=0
+    elif do_nfsmount ; then
+        NETBOOT="nfs"
+        export NETBOOT
+        rc=0
+    fi
+
+    [ "$quiet" != "y" ] && log_end_msg
+    return ${rc}
+}
+
+do_nfsmount() {
+    rc=1
+    modprobe "${MP_QUIET}" nfs
+    if [ -z "${NFSOPTS}" ]; then
+        NFSOPTS=""
+    fi
+
+    [ "$quiet" != "y" ] && log_begin_msg "Trying nfsmount -o nolock -o ro ${NFSOPTS} ${NFSROOT} ${mountpoint}"
+    # FIXME: This for loop is an ugly HACK round an nfs bug
+    for i in 0 1 2 3 4 5 6 7 8 9 a b c d e f 10 11 12 13; do
+        nfsmount -o nolock -o ro ${NFSOPTS} "${NFSROOT}" "${mountpoint}" && rc=0 && break
+        sleep 1
+    done
+    return ${rc}
+}
+
+do_cifsmount() {
+    rc=1
+    if [ -x "/sbin/mount.cifs" ]; then
+        if [ -z "${NFSOPTS}" ]; then
+            CIFSOPTS="-ouser=root,password="
         else
-            mount -t tmpfs tmpfs /cow
+            CIFSOPTS="${NFSOPTS}"
         fi
 
-       mkdir -p /rofs
-    if [ "$(get_fstype $backdev)" = "unknown" ]; then
-        panic "Unknown file system type on $backdev"
-    fi
-       mount -t $(get_fstype "$backdev") -o ro "$backdev" /rofs || panic "Can not mount $backdev on /rofs"
+        [ "$quiet" != "y" ] && log_begin_msg "Trying mount.cifs ${NFSROOT} ${mountpoint} ${CIFSOPTS}"
+        modprobe "${MP_QUIET}" cifs
 
-       mount -t unionfs -o dirs=/cow=rw:/rofs=ro unionfs "$rootmnt"
-        if grep -q show-cow /proc/cmdline; then
-            mkdir -p "$rootmnt/cow"
-            mount -o bind /cow "$rootmnt/cow"
+        if mount.cifs "${NFSROOT}" "${mountpoint}" "${CIFSOPTS}" ; then
+            rc=0
         fi
-        mkdir -p "$rootmnt/rofs"
-        mount -o bind /rofs "$rootmnt/rofs"
+    fi
+    return ${rc}
 }
 
-is_usb_device() {
-    sysfs_path="${1#/sys}"
-    if /lib/udev/path_id "${sysfs_path}" | grep -q "ID_PATH=usb"; then
+do_snap_copy ()
+{
+    fromdev="${1}"
+    todir="${2}"
+    snap_type="${3}"
+
+    size=$(used_fs_size "${fromdev}")
+
+    if [ -b "${fromdev}" ]; then
+        # look for free mem
+        if [ ! -z "${HOMEMOUNTED}" ] && [ "${snap_type}" = "HOME" ]; then
+            freespace="$(df -k ${copytodev} | grep -s ${copytodev} | awk '{print $4}')"
+        else
+            freespace=$( expr $(awk '/MemFree/{print $2}' /proc/meminfo) + $( cat /proc/meminfo | grep Cached | head -n 1 | awk '/Cached/{print $2}' - ))
+        fi
+        tomount="/mnt/tmpsnap"
+        mkdir -p "${tomount}"
+        mount -t $(get_fstype "${fromdev}") -o ro "${fromdev}" "${tomount}"
+        cp -a "${tomount}"/* ${todir}
+        umount "${tomount}"
+
+        if echo ${fromdev} | grep -qs loop; then
+            losetup -d "${fromdev}"
+        fi
+
         return 0
+    else
+        return 1
+        [ "$quiet" != "y" ] && log_warning_msg "Unable to find the snapshot ${snap_type} medium"
     fi
-    return 1
 }
 
-find_cd() {
-       mounted=
-        for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram); do
-            devname=$(sys2dev "${sysblock}")
-            fstype=$(get_fstype "${devname}")
-            if /lib/udev/cdrom_id ${devname} > /dev/null; then
-                mount -t ${fstype} -o ro "$devname" $mountpoint || continue
-                if casper_path $mountpoint; then
-                    echo $(casper_path $mountpoint)
-                    return
-                else
-                    umount $mountpoint
-                fi
-            elif is_usb_device "$sysblock"; then
-                for dev in $(subdevices "${sysblock}"); do
-                    devname=$(sys2dev "${dev}")
-                    fstype=$(get_fstype "${devname}")
-                    case ${fstype} in
-                        vfat|iso9660|udf)
-                            mount -t ${fstype} -o ro "${devname}" $mountpoint || continue
-                            if casper_path $mountpoint; then
-                                echo $(casper_path $mountpoint)
-                                return
-                            else
-                                umount $mountpoint
-                            fi
-                            ;;
-                    esac
-                done
-           elif [ "${fstype}" = "squashfs" ]; then
+try_snap ()
+{
+    snap_label="${1}"
+    snap_mount="${2}"
+    snap_type="${3}"
+
+    snapdata=$(find_files "${snap_label}.squashfs ${snap_label}.cpio.gz ${snap_label}.cpz ${snap_label}.gz")
+    if [ ! -z "${snapdata}" ]; then
+        snapdev=$(echo ${snapdata} | cut -f1 -d ' ')
+        snapback=$(echo ${snapdata} | cut -f2 -d ' ')
+        snapfile=$(echo ${snapdata} | cut -f3 -d ' ')
+        if echo "${snapfile}" | grep -qs "squashfs" ; then
+            # squashfs snapshot
+            if ! do_snap_copy $( get_backing_device "${snapback}/${snapfile}" ) "${snap_mount}" "${snap_type}"; then
+                 log_warning_msg "Impossible to include the ${snapfile} Snapshot"
+                 return 1
+            fi
+        else
+            # cpio.gz snapshot
+            if ! (cd "${snap_mount}" && zcat "${snapback}/${snapfile}" | cpio -i -u -d ) ; then
+                log_warning_msg "Impossible to include the ${snapfile} Snapshot"
+                return 1
+            fi
+        fi
+        umount "${snapback}"
+    else # try pure snapshot device better elif.. rework all that routine
+        if ! do_snap_copy $(find_cow_device "${snap_label}") "${snap_mount}" "${snap_type}"; then
+            log_warning_msg "Impossible to include the ${snap_label} Snapshot"
+            return 1
+        fi
+    fi
+    echo "export ${snap_type}SNAP=${snapdev}:${snapfile}" >> /etc/casper.conf # for resync on reboot/halt
+    return 0
+}
 
-                # This is an ugly hack situation, the block device has
-                # a squashfs image directly on it.  It's hopefully
-                # casper, so take it and run with it.
+do_others_persistences ()
+{
+    # directly mount /home
+    # FIXME: add a custom mounts configurable system
+    homecow=$(find_cow_device "${home_persistence}" )
+    if [ -b "${homecow}" ]; then
+        mount ${homecow} -t $(get_fstype "${homecow}") -o rw "${rootmnt}/home"
+        export HOMEMOUNTED=1
+    else
+        [ "$quiet" != "y" ] && log_warning_msg "Unable to find the persistent home medium"
+    fi
 
-                ln -s "${devname}" "${devname}.${fstype}"
-                echo "${devname}.${fstype}"
-                return
+    # Look for snapshots to copy in
+    try_snap "${root_snapshot}" "${rootmnt}" "ROOT"
+    try_snap "${home_snapshot}" "${rootmnt}/home" "HOME"
+}
+
+setup_unionfs() {
+    image_directory="$1"
+    rootmnt="$2"
+
+    modprobe "${MP_QUIET}" -b unionfs
+
+    # run-init can't deal with images in a subdir, but we're going to
+    # move all of these away before it runs anyway.  No, we're not,
+    # put them in / since move-mounting them into / breaks mono and
+    # some other apps.
+
+    croot="/"
+
+    # Let's just mount the read-only file systems first
+    rofsstring=""
+    rofslist=""
+    if [ "${NETBOOT}" == "nfs" ] ; then
+        roopt="nfsro" # go aroung a bug in nfs-unionfs locking
+    else
+        roopt="ro"
+    fi
+
+    mkdir -p "${croot}"
+    for image_type in "ext2" "squashfs" "dir" ; do
+        for image in "${image_directory}"/*."${image_type}"; do
+            imagename=$(basename "${image}")
+            if [ -d "${image}" ]; then
+                # it is a plain directory: do nothing
+                rofsstring="${image}=${roopt}:${rofsstring}"
+                rofslist="${image} ${rofslist}"
+            elif [ -f "${image}" ]; then
+                backdev=$(get_backing_device "$image")
+                fstype=$(get_fstype "${backdev}")
+                if [ "${fstype}" = "unknown" ]; then
+                    panic "Unknown file system type on ${backdev} (${image})"
+                fi
+                mkdir -p "${croot}/${imagename}"
+                mount -t "${fstype}" -o ro "${backdev}" "${croot}/${imagename}" || panic "Can not mount $backdev ($image) on ${croot}/${imagename}" && rofsstring="${croot}/${imagename}=${roopt}:${rofsstring}" && rofslist="${croot}/${imagename} ${rofslist}"
             fi
         done
+    done
+    rofsstring=${rofsstring%:}
+
+    mkdir -p /cow
+    cowdevice="tmpfs"
+    cow_fstype="tmpfs"
+
+    # Looking for "${root_persistence}" device or file
+    if [ ! -z "${PERSISTENT}" ]; then
+        cowprobe=$(find_cow_device "${root_persistence}")
+        if [ -b "${cowprobe}" ]; then
+            cowdevice=${cowprobe}
+            cow_fstype=$(get_fstype "${cowprobe}")
+        else
+            [ "$quiet" != "y" ] && log_warning_msg "Unable to find the persistent medium"
+        fi
+    fi
+
+    mount ${cowdevice} -t ${cow_fstype} -o rw /cow || panic "Can not mount $cowdevice on /cow"
+
+    mount -t unionfs -o dirs=/cow=rw:$rofsstring unionfs "$rootmnt" || panic "Unionfs mount failed"
+
+    # Adding other custom mounts
+    if [ ! -z "${PERSISTENT}" ]; then
+        do_others_persistences
+    fi
+
+    if [ ! -z "${SHOWMOUNTS}" ]; then
+        for d in ${rofslist}; do
+            mkdir -p "${rootmnt}/casper/${d##*/}"
+            case d in
+                *.dir) # do nothing # mount -o bind "${d}" "${rootmnt}/casper/${d##*/}"
+                    ;;
+                *) mount -o move "${d}" "${rootmnt}/casper/${d##*/}"
+                    ;;
+            esac
+        done
+    fi
+
+    # shows cow fs on /cow for use by casper-snapshot
+    mkdir -p "$rootmnt/cow"
+    mount -o bind /cow "$rootmnt/cow"
+}
+
+check_dev ()
+{
+    sysdev="${1}"
+    devname="${2}"
+    if [ -z "${devname}" ]; then
+        devname=$(sys2dev "${sysdev}")
+    fi
+    fstype=$(get_fstype "${devname}")
+    if is_supported_fs ${fstype}; then
+        mount -t ${fstype} -o ro "${devname}" $mountpoint || continue
+        if is_casper_path $mountpoint; then
+            echo $mountpoint
+            return 0
+        else
+            umount $mountpoint
+        fi
+    fi
+    return 1
+}
+
+find_livefs() {
+    # first look at the one specified in the command line
+    if [ ! -z "${LIVEMEDIA}" ]; then
+        if check_dev "null" "${LIVEMEDIA}"; then
+            return 0
+        fi
+    fi
+    # or do the scan of block devices
+    for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram); do
+        devname=$(sys2dev "${sysblock}")
+        fstype=$(get_fstype "${devname}")
+        if /lib/udev/cdrom_id ${devname} > /dev/null; then
+            if check_dev "null" "${devname}" ; then
+                return 0
+            fi
+        elif is_nice_device "${sysblock}" ; then
+            for dev in $(subdevices "${sysblock}"); do
+                if check_dev "${dev}" ; then
+                    return 0
+                fi
+            done
+        elif [ "${fstype}" = "squashfs" -o \
+                "${fstype}" = "ext3" ] -o \
+                "${fstype}" = "ext2" ]; then
+            # This is an ugly hack situation, the block device has
+            # an image directly on it.  It's hopefully
+            # casper, so take it and run with it.
+            ln -s "${devname}" "${devname}.${fstype}"
+            echo "${devname}.${fstype}"
+            return 0
+        fi
+    done
+    return 1
+}
+
+pulsate() {
+    if [ -x /sbin/usplash_write ]; then
+        /sbin/usplash_write "PULSATE"
+    fi
 }
 
 set_usplash_timeout() {
@@ -272,8 +694,11 @@ mountroot() {
     exec > casper.log
     exec 2>&1
 
+    parse_cmdline
+
     set_usplash_timeout
     [ "$quiet" != "y" ] && log_begin_msg "Running /scripts/casper-premount"
+    pulsate
     run_scripts /scripts/casper-premount
     [ "$quiet" != "y" ] && log_end_msg
 
@@ -282,24 +707,41 @@ mountroot() {
 
     set_usplash_timeout
 
-    for i in 0 1 2 3 4 5 6 7 8 9 a b c d e f 10 11 12 13; do
-        live_image=$(find_cd)
-        if [ "${live_image}" ]; then
-            break
+    if [ ! -z "${NETBOOT}" ]; then
+        if do_netmount ; then
+            livefs_root="${mountpoint}"
+        else
+            panic "Unable to find a the network rootfs live file system"
         fi
-        sleep 1
-    done
-    if [ "$?" -gt 0 ]; then
-        panic "Unable to find a CD-ROM containing a live file system"
+    else
+        # Scan local devices for the image
+        for i in 0 1 2 3 4 5 6 7 8 9 a b c d e f 10 11 12 13; do
+            livefs_root=$(find_livefs)
+            if [ ! -z "${livefs_root}" ]; then
+                break
+            fi
+            sleep 1
+        done
     fi
-    
-    setup_cow "$overlay_method" "$(get_backing_device $live_image)" "$rootmnt"
+
+    if [ -z "${livefs_root}" ]; then
+        panic "Unable to find a medium containing a live file system"
+    fi
+
+    if [ ! -z "${TORAM}" ]; then
+        copy_live_to "${livefs_root}" "ram"
+    elif [ ! -z "${TODISK}" ]; then
+        copy_live_to "${livefs_root}" "${TODISK}"
+    fi
+
+    mount_images_in_directory "${livefs_root}" "${rootmnt}"
 
     log_end_msg
 
     maybe_break casper-bottom
     [ "$quiet" != "y" ] && log_begin_msg "Running /scripts/casper-bottom"
 
+    pulsate
     run_scripts /scripts/casper-bottom
     [ "$quiet" != "y" ] && log_end_msg