scripts/casper

   1 #!/bin/sh
   2
   3 # set -e
   4
   5 export PATH=/root/usr/bin:/root/usr/sbin:/root/bin:/root/sbin:/usr/bin:/usr/sbin:/bin:/sbin
   6
   7 mountpoint=/live_media
   8
   9 root_persistence="casper-rw"
  10 home_persistence="home-rw"
  11 root_snapshot="casper-sn"
  12 home_snapshot="home-sn"
  13
  14 USERNAME="casper"
  15 USERFULLNAME="Live session user"
  16 HOST="live"
  17 BUILD_SYSTEM="Debian"
  18
  19 mkdir -p $mountpoint
  20
  21 [ -f /etc/casper.conf ] && . /etc/casper.conf
  22
  23 export USERNAME USERFULLNAME HOST BUILD_SYSTEM
  24
  25 if [ "${BUILD_SYSTEM}" == "Ubuntu" ]; then
  26     MP_QUIET="-Q"
  27 else
  28     MP_QUIET="-q"
  29 fi
  30
  31 parse_cmdline ()
  32 {
  33     # looking for casper specifics options as kernel parameters
  34     for x in $(cat /proc/cmdline); do
  35         case $x in
  36             userfullname=*)
  37                 export USERFULLNAME=${x#userfullname=}
  38                 export CASPERCONF="changed"
  39                 ;;
  40             host=*)
  41                 export HOST=${x#host=}
  42                 export CASPERCONF="changed"
  43                 ;;
  44             username=*)
  45                 export USERNAME=${x#username=}
  46                 export CASPERCONF="changed"
  47                 ;;
  48             netboot*)
  49                 export NETBOOT=${x#netboot=} ;;
  50             toram)
  51                 export TORAM=1 ;;
  52             todisk=)
  53                 export TODISK=${x#todisk=} ;;
  54             showmounts)
  55                 export SHOWMOUNTS=1 ;;
  56             persistent)
  57                 export PERSISTENT=1 ;;
  58             ip*)
  59                 STATICIP=${x#ip=}
  60                 if [ "${STATICIP}" == "" ]; then
  61                     STATICIP="frommedia"
  62                 fi
  63                 export STATICIP ;;
  64             casper-getty)
  65                 export CASPERGETTY=1 ;;
  66             console=*)
  67                 export DEFCONSOLE=$(sed -e 's%.*console=%console=%' /proc/cmdline) ;;
  68             bootfrom=*)
  69                 export LIVEMEDIA=${x#bootfrom=} ;;
  70             live-media=*)
  71                 export LIVEMEDIA=${x#live-media=} ;;
  72             debian-installer/locale=*)
  73                 export LOCALE=${x#debian-installer/locale=} ;;
  74             locale=*)
  75                 export LOCALE=${x#locale=} ;;
  76             kbd-chooser/method=*)
  77                 export KBD=${x#kbd-chooser/method=} ;;
  78             keyb=*)
  79                 export KBD=${x#kbd=} ;;
  80             console-setup/layoutcode=*)
  81                 export CSLAYOUT=${x#console-setup/layoutcode=} ;;
  82             console-setup/variantcode=*)
  83                 export CSVARIANT=${x#console-setup/variantcode=} ;;
  84             console-setup/modelcode=*)
  85                 export CSMODEL=${x#console-setup/modelcode=} ;;
  86         esac
  87     done
  88
  89     # sort of compatibility with netboot.h from linux docs
  90     if [ -z "${NETBOOT}" ]; then
  91         if [ "${ROOT}" == "/dev/nfs" ]; then
  92             NETBOOT="nfs"
  93             export NETBOOT
  94         elif [ "${ROOT}" == "/dev/cifs" ]; then
  95             NETBOOT="cifs"
  96             export NETBOOT
  97         fi
  98     fi
  99 }
 100
 101 is_casper_path() {
 102     path=$1
 103     if [ -d "$path/casper" ]; then
 104         if [ "$(echo $path/casper/*.cloop)" != "$path/casper/*.cloop" ] ||
 105             [ "$(echo $path/casper/*.squashfs)" != "$path/casper/*.squashfs" ] ||
 106             [ "$(echo $path/casper/*.ext2)" != "$path/casper/*.ext2" ] ||
 107             [ "$(echo $path/casper/*.dir)" != "$path/casper/*.dir" ]; then
 108             return 0
 109         fi
 110     fi
 111     return 1
 112 }
 113
 114 subdevices() {
 115     sysblock=$1
 116     r=""
 117     for dev in "${sysblock}" "${sysblock}"/*; do
 118         if [ -e "${dev}/dev" ]; then
 119             r="${r} ${dev}"
 120         fi
 121     done
 122     echo ${r}
 123 }
 124
 125 get_backing_device() {
 126     case "$1" in
 127         *.cloop)
 128             echo $(setup_loop "$1" "cloop" "/sys/block/cloop*")
 129             ;;
 130         *.squashfs|*.ext2)
 131             echo $(setup_loop "$1" "loop" "/sys/block/loop*")
 132             ;;
 133         *.dir)
 134             echo "directory"
 135             ;;
 136         *)
 137             panic "Unrecognized casper filesystem: $1"
 138             ;;
 139     esac
 140 }
 141
 142 match_files_in_dir() {
 143     # Does any files match pattern $1 ?
 144
 145     local pattern="$1"
 146     if [ "$(echo $pattern)" != "$pattern" ]; then
 147         return 0
 148     fi
 149     return 1
 150 }
 151
 152 mount_images_in_directory() {
 153     directory="$1"
 154     rootmnt="$2"
 155     if match_files_in_dir "$directory/casper/*.cloop"; then
 156         # Let's hope there's just one matching *.cloop... FIXME
 157         setup_devmapper $(get_backing_device "$directory/casper/*.cloop") "$rootmnt"
 158     elif match_files_in_dir "$directory/casper/*.squashfs" ||
 159         match_files_in_dir "$directory/casper/*.ext2" ||
 160         match_files_in_dir "$directory/casper/*.dir"; then
 161         setup_unionfs "$directory/casper" "$rootmnt"
 162     else
 163         :
 164     fi
 165 }
 166
 167 sys2dev() {
 168     sysdev=${1#/sys}
 169     echo "/dev/$(udevinfo -q name -p ${sysdev} 2>/dev/null|| echo ${sysdev##*/})"
 170 }
 171
 172 setup_loop() {
 173     local fspath=$1
 174     local module=$2
 175     local pattern=$3
 176
 177     modprobe "${MP_QUIET}" -b "$module"
 178     udevsettle
 179
 180     for loopdev in $pattern; do
 181         if [ "$(cat $loopdev/size)" -eq 0 ]; then
 182             dev=$(sys2dev "${loopdev}")
 183             losetup "$dev" "$fspath"
 184             echo "$dev"
 185             return 0
 186         fi
 187     done
 188     panic "No loop devices available"
 189 }
 190
 191 get_fstype() {
 192     local FSTYPE
 193     local FSSIZE
 194     eval $(fstype < $1)
 195     if [ "$FSTYPE" != "unknown" ]; then
 196         echo $FSTYPE
 197         return 0
 198     fi
 199     /lib/udev/vol_id -t $1 2>/dev/null
 200 }
 201
 202 setup_devmapper() {
 203     backdev="$1"
 204     rootmnt="$2"
 205
 206     modprobe "${MP_QUIET}" -b dm-mod
 207     COW_DEVICE=/dev/ram1
 208     COW_NAME="casper-cow"
 209
 210     BACKING_FILE_SIZE=$(blockdev --getsize "$backdev")
 211     MAX_COW_SIZE=$(blockdev --getsize "$COW_DEVICE")
 212     CHUNK_SIZE=8 # sectors
 213
 214     if [ -z "$COW_SIZE" -o "$COW_SIZE" -gt "$MAX_COW_SIZE" ]; then
 215         COW_SIZE=$MAX_COW_SIZE
 216     fi
 217
 218     echo "0 $COW_SIZE linear $COW_DEVICE 0" | dmsetup create $COW_NAME
 219
 220     echo "0 $BACKING_FILE_SIZE snapshot $backdev /dev/mapper/$COW_NAME p $CHUNK_SIZE" | \
 221         dmsetup create casper-snapshot
 222     if [ "$(get_fstype $backdev)" = "unknown" ]; then
 223         panic "Unknown file system type on $backdev"
 224     fi
 225     mount -t $(get_fstype "$backdev") /dev/mapper/casper-snapshot $rootmnt || panic "Can not mount /dev/mapper/casper/snapshot on $rootmnt"
 226
 227     mkdir -p "$rootmnt/rofs"
 228     echo "0 $BACKING_FILE_SIZE linear $backdev 0" | dmsetup create casper-backing
 229     mount -t $(get_fstype "$backdev") /dev/mapper/casper-backing "$rootmnt/rofs"
 230 }
 231
 232 is_nice_device() {
 233     sysfs_path="${1#/sys}"
 234     if /lib/udev/path_id "${sysfs_path}" | grep -E -q "ID_PATH=(usb|pci-[^-]*-[ide|scsi|usb])"; then
 235         return 0
 236     fi
 237     return 1
 238 }
 239
 240 is_supported_fs ()
 241 {
 242     # FIXME: do something better like the scan of supported filesystems
 243     fstype="${1}"
 244     case ${fstype} in
 245         vfat|iso9660|udf|ext2|ext3|ntfs)
 246             return 0
 247             ;;
 248     esac
 249     return 1
 250 }
 251
 252 where_is_mounted() {
 253     device=$1
 254     if grep -q "^$device " /proc/mounts; then
 255         grep "^$device " /proc/mounts | read d mountpoint rest
 256         echo $mountpoint
 257         return 0
 258     fi
 259     return 1
 260 }
 261
 262 used_fs_size ()
 263 {
 264     # Returns used fs kbytes + 5% more
 265     # You could pass a block device as $1 or the mount point as $2
 266
 267     dev="${1}"
 268     mountp="${2}"
 269
 270     if [ -z "${mountp}" ]; then
 271         mountp=$(where_is_mounted "${dev}")
 272         if [ "$?" -gt 0 ]; then
 273             mountp=/mnt/tmp_fs_size
 274             mkdir -p "${mountp}"
 275             mount -t $(get_fstype "${dev}") -o ro "${dev}" "${mountp}"
 276             doumount=1
 277         fi
 278     fi
 279
 280     size=$(du -ks ${mountp} | cut -f1)
 281     size=$(expr ${size} + ${size}/20 ) # FIXME: 5% more to be sure
 282     needed_space=$(expr ${size} * 1024)
 283
 284     if [ ! -z "${doumount}" ]; then
 285         umount "${mountp}"
 286         rmdir "${mountp}"
 287     fi
 288     echo "${needed_space}"
 289 }
 290
 291 copy_live_to() {
 292     copyfrom="${1}"
 293     copytodev="${2}"
 294     copyto="${copyfrom}_swap"
 295
 296     size=$(used_fs_size "null" "${copyfrom}")
 297
 298     if [ "${copytodev}" = "ram" ]; then
 299         # copying to ram:
 300         freespace=$( expr $(awk '/MemFree/{print $2}' /proc/meminfo) + $( cat /proc/meminfo | grep Cached | head -n 1 | awk '/Cached/{print $2}' - ) )
 301         mount_options="-o size=${size}k"
 302         free_string="memory"
 303         fstype="tmpfs"
 304         dev="/dev/shm"
 305     else
 306         # it should be a writable block device
 307         if [ -b "${copytodev}" ]; then
 308             free_string="space"
 309             freespace="$(df -k ${copytodev} | grep -s ${copytodev} | awk '{print $4}')"
 310             fstype="$(get_fstype ${devname})"
 311             dev="${copytodev}"
 312         else
 313             return 1
 314         fi
 315     fi
 316     if [ ! ${freespace} -lt ${size}  ] ; then
 317         [ "$quiet" != "y" ] && log_begin_msg "Not enough free ${free_string} to copy live media in ${copytodev}."
 318         [ "$quiet" != "y" ] && log_end_msg
 319         return 1
 320     fi
 321
 322     # begin copying..
 323     [ "$quiet" != "y" ] && log_begin_msg "Copying live media to ${copytodev}..."
 324     mkdir "${copyto}"
 325     mount -t "${fstype}" ${mount_options} "${dev}" "${copyto}"
 326     cp -a ${copyfrom}/* ${copyto} # "cp -a" from busybox also copies hidden files
 327     umount ${copyfrom}
 328     mount -r -o move ${copyto} ${copyfrom}
 329     rmdir ${copyto}
 330     [ "$quiet" != "y" ] && log_end_msg
 331     return 0
 332 }
 333
 334 try_mount ()
 335 {
 336     dev="${1}"
 337     mountp="${2}"
 338     opts="${3}"
 339
 340     if where_is_mounted ${dev} > /dev/null; then
 341         mount -o remount,"${opts}" ${dev} $(where_is_mounted ${dev}) || panic "Remounting failed"
 342         mount -o bind $(where_is_mounted ${dev}) ${mountp} || panic "Cannot bind-mount"
 343     else
 344         mount -t $(get_fstype "${dev}") -o "${opts}" "${dev}" "${mountp}" || panic "Cannot mount ${dev} on ${mountp}"
 345     fi
 346 }
 347
 348 find_cow_device() {
 349     pers_label="${1}"
 350     cow_backing="/${pers_label}-backing"
 351     for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop); do
 352         for dev in $(subdevices "${sysblock}"); do
 353             devname=$(sys2dev "${dev}")
 354             if [ "$(/lib/udev/vol_id -l $devname 2>/dev/null)" = "${pers_label}" ]; then
 355                 echo "$devname"
 356                 return
 357             elif [ "$(get_fstype ${devname})" = "vfat" ]; then # FIXME: all supported block devices should be scanned
 358                 mkdir -p "${cow_backing}"
 359                 try_mount "${devname}" "${cow_backing}" "rw"
 360                 if [ -e "${cow_backing}/${pers_label}" ]; then
 361                     echo $(setup_loop "${cow_backing}/${pers_label}" "loop" "/sys/block/loop*")
 362                     return 0
 363                 else
 364                     umount ${cow_backing}
 365                 fi
 366             fi
 367         done
 368     done
 369 }
 370
 371 find_files()
 372 # return the first of $filenames found on vfat and ext2 devices
 373 # FIXME: merge with above function
 374 {
 375     filenames="${1}"
 376     snap_backing="/snap-backing"
 377     for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop); do
 378         for dev in $(subdevices "${sysblock}"); do
 379             devname=$(sys2dev "${dev}")
 380             devfstype="$(get_fstype ${devname})"
 381             if [ "${devfstype}" = "vfat" ] ||  [ "${devfstype}" = "ext2" ] ; then # FIXME: all supported block devices should be scanned
 382                 mkdir -p "${snap_backing}"
 383                 try_mount "${devname}" "${snap_backing}" "ro"
 384                 for filename in ${filenames}; do
 385                     if [ -e "${snap_backing}/${filename}" ]; then
 386                         echo "${devname} ${snap_backing} ${filename}"
 387                         return 0
 388                     fi
 389                 done
 390                 umount ${snap_backing}
 391             fi
 392         done
 393     done
 394 }
 395
 396 do_netmount() {
 397     rc=1
 398
 399     modprobe "${MP_QUIET}" af_packet # For DHCP
 400
 401     ipconfig ${DEVICE} /tmp/net-${DEVICE}.conf
 402
 403     if [ "${NFSROOT}" = "auto" ]; then
 404         NFSROOT=${ROOTSERVER}:${ROOTPATH}
 405     fi
 406
 407     [ "$quiet" != "y" ] && log_begin_msg "Trying netboot from ${NFSROOT}"
 408
 409     if [ "${NETBOOT}" != "nfs" ] && do_cifsmount ; then
 410         rc=0
 411     elif do_nfsmount ; then
 412         NETBOOT="nfs"
 413         export NETBOOT
 414         rc=0
 415     fi
 416
 417     [ "$quiet" != "y" ] && log_end_msg
 418     return ${rc}
 419 }
 420
 421 do_nfsmount() {
 422     rc=1
 423     modprobe "${MP_QUIET}" nfs
 424     if [ -z "${NFSOPTS}" ]; then
 425         NFSOPTS=""
 426     fi
 427
 428     [ "$quiet" != "y" ] && log_begin_msg "Trying nfsmount -o nolock -o ro ${NFSOPTS} ${NFSROOT} ${mountpoint}"
 429     # FIXME: This for loop is an ugly HACK round an nfs bug
 430     for i in 0 1 2 3 4 5 6 7 8 9 a b c d e f 10 11 12 13; do
 431         nfsmount -o nolock -o ro ${NFSOPTS} "${NFSROOT}" "${mountpoint}" && rc=0 && break
 432         sleep 1
 433     done
 434     return ${rc}
 435 }
 436
 437 do_cifsmount() {
 438     rc=1
 439     if [ -x "/sbin/mount.cifs" ]; then
 440         if [ -z "${NFSOPTS}" ]; then
 441             CIFSOPTS="-ouser=root,password="
 442         else
 443             CIFSOPTS="${NFSOPTS}"
 444         fi
 445
 446         [ "$quiet" != "y" ] && log_begin_msg "Trying mount.cifs ${NFSROOT} ${mountpoint} ${CIFSOPTS}"
 447         modprobe "${MP_QUIET}" cifs
 448
 449         if mount.cifs "${NFSROOT}" "${mountpoint}" "${CIFSOPTS}" ; then
 450             rc=0
 451         fi
 452     fi
 453     return ${rc}
 454 }
 455
 456 do_snap_copy ()
 457 {
 458     fromdev="${1}"
 459     todir="${2}"
 460     snap_type="${3}"
 461
 462     size=$(used_fs_size "${fromdev}")
 463
 464     if [ -b "${fromdev}" ]; then
 465         # look for free mem
 466         if [ ! -z "${HOMEMOUNTED}" ] && [ "${snap_type}" = "HOME" ]; then
 467             freespace="$(df -k ${copytodev} | grep -s ${copytodev} | awk '{print $4}')"
 468         else
 469             freespace=$( expr $(awk '/MemFree/{print $2}' /proc/meminfo) + $( cat /proc/meminfo | grep Cached | head -n 1 | awk '/Cached/{print $2}' - ))
 470         fi
 471         tomount="/mnt/tmpsnap"
 472         mkdir -p "${tomount}"
 473         mount -t $(get_fstype "${fromdev}") -o ro "${fromdev}" "${tomount}"
 474         cp -a "${tomount}"/* ${todir}
 475         umount "${tomount}"
 476
 477         if echo ${fromdev} | grep -qs loop; then
 478             losetup -d "${fromdev}"
 479         fi
 480
 481         return 0
 482     else
 483         return 1
 484         [ "$quiet" != "y" ] && log_warning_msg "Unable to find the snapshot ${snap_type} medium"
 485     fi
 486 }
 487
 488 try_snap ()
 489 {
 490     snap_label="${1}"
 491     snap_mount="${2}"
 492     snap_type="${3}"
 493
 494     snapdata=$(find_files "${snap_label}.squashfs ${snap_label}.cpio.gz ${snap_label}.cpz ${snap_label}.gz")
 495     if [ ! -z "${snapdata}" ]; then
 496         snapdev=$(echo ${snapdata} | cut -f1 -d ' ')
 497         snapback=$(echo ${snapdata} | cut -f2 -d ' ')
 498         snapfile=$(echo ${snapdata} | cut -f3 -d ' ')
 499         if echo "${snapfile}" | grep -qs "squashfs" ; then
 500             # squashfs snapshot
 501             if ! do_snap_copy $( get_backing_device "${snapback}/${snapfile}" ) "${snap_mount}" "${snap_type}"; then
 502                  log_warning_msg "Impossible to include the ${snapfile} Snapshot"
 503                  return 1
 504             fi
 505         else
 506             # cpio.gz snapshot
 507             if ! (cd "${snap_mount}" && zcat "${snapback}/${snapfile}" | cpio -i -u -d ) ; then
 508                 log_warning_msg "Impossible to include the ${snapfile} Snapshot"
 509                 return 1
 510             fi
 511         fi
 512         umount "${snapback}"
 513     else # try pure snapshot device better elif.. rework all that routine
 514         if ! do_snap_copy $(find_cow_device "${snap_label}") "${snap_mount}" "${snap_type}"; then
 515             log_warning_msg "Impossible to include the ${snap_label} Snapshot"
 516             return 1
 517         fi
 518     fi
 519     echo "export ${snap_type}SNAP=${snapdev}:${snapfile}" >> /etc/casper.conf # for resync on reboot/halt
 520     return 0
 521 }
 522
 523 do_others_persistences ()
 524 {
 525     # directly mount /home
 526     # FIXME: add a custom mounts configurable system
 527     homecow=$(find_cow_device "${home_persistence}" )
 528     if [ -b "${homecow}" ]; then
 529         mount ${homecow} -t $(get_fstype "${homecow}") -o rw "${rootmnt}/home"
 530         export HOMEMOUNTED=1
 531     else
 532         [ "$quiet" != "y" ] && log_warning_msg "Unable to find the persistent home medium"
 533     fi
 534
 535     # Look for snapshots to copy in
 536     try_snap "${root_snapshot}" "${rootmnt}" "ROOT"
 537     try_snap "${home_snapshot}" "${rootmnt}/home" "HOME"
 538 }
 539
 540 setup_unionfs() {
 541     image_directory="$1"
 542     rootmnt="$2"
 543
 544     modprobe "${MP_QUIET}" -b unionfs
 545
 546     # run-init can't deal with images in a subdir, but we're going to
 547     # move all of these away before it runs anyway.  No, we're not,
 548     # put them in / since move-mounting them into / breaks mono and
 549     # some other apps.
 550
 551     croot="/"
 552
 553     # Let's just mount the read-only file systems first
 554     rofsstring=""
 555     rofslist=""
 556     if [ "${NETBOOT}" == "nfs" ] ; then
 557         roopt="nfsro" # go aroung a bug in nfs-unionfs locking
 558     else
 559         roopt="ro"
 560     fi
 561
 562     mkdir -p "${croot}"
 563     for image_type in "ext2" "squashfs" "dir" ; do
 564         for image in "${image_directory}"/*."${image_type}"; do
 565             imagename=$(basename "${image}")
 566             if [ -d "${image}" ]; then
 567                 # it is a plain directory: do nothing
 568                 rofsstring="${image}=${roopt}:${rofsstring}"
 569                 rofslist="${image} ${rofslist}"
 570             elif [ -f "${image}" ]; then
 571                 backdev=$(get_backing_device "$image")
 572                 fstype=$(get_fstype "${backdev}")
 573                 if [ "${fstype}" = "unknown" ]; then
 574                     panic "Unknown file system type on ${backdev} (${image})"
 575                 fi
 576                 mkdir -p "${croot}/${imagename}"
 577                 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} ${rofslist}"
 578             fi
 579         done
 580     done
 581     rofsstring=${rofsstring%:}
 582
 583     mkdir -p /cow
 584     cowdevice="tmpfs"
 585     cow_fstype="tmpfs"
 586
 587     # Looking for "${root_persistence}" device or file
 588     if [ ! -z "${PERSISTENT}" ]; then
 589         cowprobe=$(find_cow_device "${root_persistence}")
 590         if [ -b "${cowprobe}" ]; then
 591             cowdevice=${cowprobe}
 592             cow_fstype=$(get_fstype "${cowprobe}")
 593         else
 594             [ "$quiet" != "y" ] && log_warning_msg "Unable to find the persistent medium"
 595         fi
 596     fi
 597
 598     mount ${cowdevice} -t ${cow_fstype} -o rw /cow || panic "Can not mount $cowdevice on /cow"
 599
 600     mount -t unionfs -o dirs=/cow=rw:$rofsstring unionfs "$rootmnt" || panic "Unionfs mount failed"
 601
 602     # Adding other custom mounts
 603     if [ ! -z "${PERSISTENT}" ]; then
 604         do_others_persistences
 605     fi
 606
 607     if [ ! -z "${SHOWMOUNTS}" ]; then
 608         for d in ${rofslist}; do
 609             mkdir -p "${rootmnt}/casper/${d##*/}"
 610             case d in
 611                 *.dir) # do nothing # mount -o bind "${d}" "${rootmnt}/casper/${d##*/}"
 612                     ;;
 613                 *) mount -o move "${d}" "${rootmnt}/casper/${d##*/}"
 614                     ;;
 615             esac
 616         done
 617     fi
 618
 619     # shows cow fs on /cow for use by casper-snapshot
 620     mkdir -p "$rootmnt/cow"
 621     mount -o bind /cow "$rootmnt/cow"
 622 }
 623
 624 check_dev ()
 625 {
 626     sysdev="${1}"
 627     devname="${2}"
 628     if [ -z "${devname}" ]; then
 629         devname=$(sys2dev "${sysdev}")
 630     fi
 631     fstype=$(get_fstype "${devname}")
 632     if is_supported_fs ${fstype}; then
 633         mount -t ${fstype} -o ro "${devname}" $mountpoint || continue
 634         if is_casper_path $mountpoint; then
 635             echo $mountpoint
 636             return 0
 637         else
 638             umount $mountpoint
 639         fi
 640     fi
 641     return 1
 642 }
 643
 644 find_livefs() {
 645     # first look at the one specified in the command line
 646     if [ ! -z "${LIVEMEDIA}" ]; then
 647         if check_dev "null" "${LIVEMEDIA}"; then
 648             return 0
 649         fi
 650     fi
 651     # or do the scan of block devices
 652     for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram); do
 653         devname=$(sys2dev "${sysblock}")
 654         fstype=$(get_fstype "${devname}")
 655         if /lib/udev/cdrom_id ${devname} > /dev/null; then
 656             if check_dev "null" "${devname}" ; then
 657                 return 0
 658             fi
 659         elif is_nice_device "${sysblock}" ; then
 660             for dev in $(subdevices "${sysblock}"); do
 661                 if check_dev "${dev}" ; then
 662                     return 0
 663                 fi
 664             done
 665         elif [ "${fstype}" = "squashfs" -o \
 666                 "${fstype}" = "ext3" ] -o \
 667                 "${fstype}" = "ext2" ]; then
 668             # This is an ugly hack situation, the block device has
 669             # an image directly on it.  It's hopefully
 670             # casper, so take it and run with it.
 671             ln -s "${devname}" "${devname}.${fstype}"
 672             echo "${devname}.${fstype}"
 673             return 0
 674         fi
 675     done
 676     return 1
 677 }
 678
 679 pulsate() {
 680     if [ -x /sbin/usplash_write ]; then
 681         /sbin/usplash_write "PULSATE"
 682     fi
 683 }
 684
 685 set_usplash_timeout() {
 686     if [ -x /sbin/usplash_write ]; then
 687         /sbin/usplash_write "TIMEOUT 120"
 688     fi
 689 }
 690
 691 mountroot() {
 692     exec 6>&1
 693     exec 7>&2
 694     exec > casper.log
 695     exec 2>&1
 696
 697     parse_cmdline
 698
 699     set_usplash_timeout
 700     [ "$quiet" != "y" ] && log_begin_msg "Running /scripts/casper-premount"
 701     pulsate
 702     run_scripts /scripts/casper-premount
 703     [ "$quiet" != "y" ] && log_end_msg
 704
 705     # Needed here too because some things (*cough* udev *cough*)
 706     # changes the timeout
 707
 708     set_usplash_timeout
 709
 710     if [ ! -z "${NETBOOT}" ]; then
 711         if do_netmount ; then
 712             livefs_root="${mountpoint}"
 713         else
 714             panic "Unable to find a the network rootfs live file system"
 715         fi
 716     else
 717         # Scan local devices for the image
 718         for i in 0 1 2 3 4 5 6 7 8 9 a b c d e f 10 11 12 13; do
 719             livefs_root=$(find_livefs)
 720             if [ ! -z "${livefs_root}" ]; then
 721                 break
 722             fi
 723             sleep 1
 724         done
 725     fi
 726
 727     if [ -z "${livefs_root}" ]; then
 728         panic "Unable to find a medium containing a live file system"
 729     fi
 730
 731     if [ ! -z "${TORAM}" ]; then
 732         copy_live_to "${livefs_root}" "ram"
 733     elif [ ! -z "${TODISK}" ]; then
 734         copy_live_to "${livefs_root}" "${TODISK}"
 735     fi
 736
 737     mount_images_in_directory "${livefs_root}" "${rootmnt}"
 738
 739     log_end_msg
 740
 741     maybe_break casper-bottom
 742     [ "$quiet" != "y" ] && log_begin_msg "Running /scripts/casper-bottom"
 743
 744     pulsate
 745     run_scripts /scripts/casper-bottom
 746     [ "$quiet" != "y" ] && log_end_msg
 747
 748     exec 1>&6 6>&-
 749     exec 2>&7 7>&-
 750     cp casper.log "${rootmnt}/var/log/"
 751 }