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|
#!/bin/busybox ash
# Install busybox's applets as symlinks
/bin/busybox --install -s
. /init_functions
msg ":: Loading Initramfs"
/bin/mount -t proc proc /proc
/bin/mount -t sysfs sys /sys
read CMDLINE </proc/cmdline
export CMDLINE
export root=""
export init=""
echo "/sbin/modprobe" > /proc/sys/kernel/modprobe
# set default mount handler
mount_handler="default"
# if available, start udevd at this stage
if [ -x /sbin/udevd ]; then
msg ":: Starting udevd..."
echo > /proc/sys/kernel/hotplug
/sbin/udevd --daemon --resolve-names=never
msg "done."
fi
for cmd in ${CMDLINE}; do
case "${cmd}" in
\#*) break ;; # ignore everything after a # in the commandline
# The kernel passes those to the kernel on its own
[0123456Ss]) ;;
[0-9]*) ;;
single) ;;
rw) readwrite="yes" ;;
ro) readwrite="no" ;;
# only export stuff that does work with ash :)
*=*) rhs="$(echo "${cmd}" | cut -d= -f2-)"
cmd="$(echo "${cmd}" | cut -d= -f1 | sed 's|\.|_|g')"
cmd="$(echo "${cmd}" | sed 's|-|_|g')=${rhs}"
(echo "${cmd}" | grep -qe '^[0-9]') || export "${cmd}"
;;
*) cmd="$(echo "${cmd}" | sed 's|\.|_|g')"
cmd="$(echo "${cmd}" | sed 's|-|_|g')"
(echo "${cmd}" | grep -qe '^[0-9]') || export "${cmd}=y"
;;
esac
done
if [ -n "${disablehooks}" ]; then
for d in $(echo "${disablehooks}" | sed 's|,| |g'); do
export "hook_${d}=disabled"
done
fi
if [ -n "${disablemodules}" ]; then
for d in $(echo "${disablemodules}" | sed 's|,| |g'); do
export "mod_${d}=disabled"
done
fi
if [ -n "${earlymodules}" ]; then
for m in $(echo "${earlymodules}" | sed 's|,| |g'); do
/sbin/modprobe -q ${m} > /dev/null 2>&1
done
fi
. /config
for m in ${MODULES}; do
TST=""
eval "TST=\$mod_${m}"
if [ "${TST}" != "disabled" ]; then
/sbin/modprobe -q ${m} > /dev/null 2>&1
fi
done
# If rootdelay is empty or not a non-negative integer, set it to 10
if [ -z "${rootdelay}" ] || ! [ "${rootdelay}" -ge 0 ]; then
export rootdelay=10
fi
if [ -e "/hooks" ]; then
for h in ${HOOKS}; do
TST=""
eval "TST=\$hook_${h}"
if [ "${TST}" != "disabled" ]; then
run_hook () { msg "${h}: no run function defined"; }
if [ -e "/hooks/${h}" ]; then
. /hooks/${h}
msg ":: Running Hook [${h}]"
run_hook
fi
fi
done
fi
if [ "${break}" = "y" ]; then
echo ":: Break requested, type 'exit' to resume operation"
launch_interactive_shell
fi
if [ -f "/message" ]; then
msg "$(cat /message)"
fi
mkdir -p /new_root
if [ -z "${mount_handler}" -o "${mount_handler}" = "default" ]; then
if [ ${root:0:5} != "/dev/" ] || ! poll_device "${root}" ${rootdelay}; then
msg "\nRoot device '${root}' doesn't exist. Attempting to create it."
rootdev=""
if [ ${root:0:5} = "/dev/" ]; then
# It might be a block device (/dev/sda)
if [ -f /sys/block/${root:5}/dev ]; then
rootdev="$(cat /sys/block/${root:5}/dev | sed 's|:| |')"
# It might be a partition on any block device (/dev/sda1)
else
for dir in /sys/block/*; do
if [ -f ${dir}/${root:5}/dev ]; then
rootdev="$(cat ${dir}/${root:5}/dev | sed 's|:| |')"
break
fi
done
fi
# It might be a major/minor pair (8:1)
elif echo ${root} | grep -q :; then
rootdev="$(echo ${root} | sed 's|:| |')"
root="/dev/root"
# It might be major/minor encoded as a single hex-number (lilo-style) (801)
elif [ ${#root} -le 4 -a ${#root} -gt 2 ] && echo "${root}" | grep -qe '^[A-Fa-f0-9]*$'; then
str_offset=$((${#root}-2))
major=$(printf "%d" 0x${root:0:${str_offset}})
minor=$(printf "%d" 0x${root:${str_offset}})
rootdev="${major} ${minor}"
root="/dev/root"
fi
if [ -n "${rootdev}" ]; then
msg "Creating root device ${root} with major $(echo "${rootdev}" | cut -d\ -f1) and minor $(echo "${rootdev}" | cut -d\ -f2)."
mknod ${root} b ${rootdev}
else
err "Unable to determine major/minor number of root device '${root}'."
echo "You are being dropped to a recovery shell"
echo " Type 'exit' to try and continue booting"
launch_interactive_shell
msg "Trying to continue (this will most likely fail) ..."
fi
fi
# We didn't build filesystem support into busybox,
# instead we use util-linux-ng's blkid for best compatibility
if [ -n "${rootfstype}" ]; then
fstype="${rootfstype}"
else
fstype=$(eval $(/sbin/blkid -o udev -p "${root}"); echo $ID_FS_TYPE)
if [ -z "${fstype}" ]; then
err "Unable to determine the file system type of ${root}:"
echo "Either it contains no filesystem, an unknown filesystem,"
echo "or more than one valid file system signature was found."
echo
echo "Try adding"
echo " rootfstype=your_filesystem_type"
echo "to the kernel command line."
echo
echo "You are now being dropped into an emergency shell."
launch_interactive_shell
msg "Trying to continue (this will most likely fail) ..."
fi
fi
if [ "${readwrite}" = "yes" ]; then
rwopt="rw"
else
rwopt="ro"
fi
mount ${fstype:+-t ${fstype}} -o ${rwopt}${rootflags:+,${rootflags}} "${root}" /new_root
else
${mount_handler} /new_root
fi
[ -z "${init}" ] && init="/sbin/init"
if [ "$(stat -f -c %i /)" = "$(stat -f -c %i /new_root)" ]; then
# Nothing got mounted on /new_root. This is the end, we don't know what to do anymore
# We fall back into a shell, but the shell has now PID 1
# This way, manual recovery is still possible.
err "Failed to mount the real root device."
echo "Bailing out, you are on your own. Good luck."
echo
launch_interactive_shell --exec
elif [ ! -f "/new_root${init}" ]; then
# Successfully mounted /new_root, but ${init} is missing
# The same logic as above applies
err "Root device mounted successfully, but ${init} does not exist."
echo "Bailing out, you are on your own. Good luck."
echo
launch_interactive_shell --exec
fi
#Special handling if udev is running
udevpid=$(/bin/pidof udevd)
if [ -n "${udevpid}" ]; then
# Settle pending uevents, then kill udev
/sbin/udevadm settle
/bin/kill ${udevpid} > /dev/null 2>&1
while /bin/pidof udevd >/dev/null; do
sleep 0.1
done
fi
umount /proc
umount /sys
exec /sbin/switch_root -c /dev/console /new_root ${init} "$@"
|
