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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
if grep -q devtmpfs /proc/filesystems 2>/dev/null; then
/bin/mount -n -t devtmpfs udev /dev -o mode=0755,size=10M,nosuid
else
/bin/mount -n -t tmpfs udev /dev -o mode=0755,size=10M,nosuid
# We don't have devtmpfs, so add the most important standard devices
/bin/mknod /dev/null c 1 3
/bin/mknod /dev/zero c 1 5
/bin/mknod /dev/console c 5 1
# /dev/mem is needed if we want to load uvesafb before triggering uevents
/bin/mknod /dev/mem c 1 1
fi
read CMDLINE </proc/cmdline
export CMDLINE
export root=""
export init=""
echo "/sbin/modprobe" > /proc/sys/kernel/modprobe
# set default mount handler
mount_handler="default_mount_handler"
# 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
export udevd_running=1
msg "done."
else
export udevd_running=0
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
# Mount root at /new_root
mkdir -p /new_root
${mount_handler} /new_root
[ -z "${init}" ] && init="/sbin/init"
if [ "$(stat -c %D /)" = "$(stat -c %D /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 [ ! -x "/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
mount --move /proc /new_root/proc
mount --move /sys /new_root/sys
mount --move /dev /new_root/dev
exec /sbin/switch_root -c /dev/console /new_root ${init} "$@"
|
