#!/bin/sh -e
### BEGIN INIT INFO
# Provides:          udev
# Required-Start:    mountkernfs
# Required-Stop:
# Default-Start:     S
# Default-Stop:
# Short-Description: Start udevd, populate /dev and load drivers.
### END INIT INFO

# This script is based on Debian's.

COLDPLUG=no
COLDPLUG_TARBALL="/lib/udev/devices.tar.gz"

for x in $(cat /proc/cmdline); do
        case $x in
        coldplug)
		COLDPLUG=yes
                ;;
        esac
done

# we need to unmount /dev/pts/ and remount it later over the tmpfs
unmount_devpts() {
  if mountpoint -q /dev/pts/; then
    umount -n -l /dev/pts/
  fi

  if mountpoint -q /dev/shm/; then
    umount -n -l /dev/shm/
  fi
}

# mount a tmpfs over /dev, if somebody did not already do it
mount_tmpfs() {
  if grep -q "/dev tmpfs" /proc/mounts; then
    return
  fi

  if ! mount -n -o size=$tmpfs_size,mode=0755 -t tmpfs udev /dev; then
    echo "udev requires tmpfs support, not started."
    exit 1
  fi

  return 0
}

create_dev_makedev() {
  if [ -e /sbin/MAKEDEV ]; then
    ln -sf /sbin/MAKEDEV /dev/MAKEDEV
  else
    ln -sf /bin/true /dev/MAKEDEV
  fi
}

make_extra_nodes() {
  ret=1
  if [ "$(echo /lib/udev/devices/*)" != "/lib/udev/devices/*" ]; then
    cp -a /lib/udev/devices/* /$1/
    ret=0
  fi

  [ -e /etc/udev/links.conf ] || return $ret

  grep '^[^#]' /etc/udev/links.conf | \
  while read type name arg1; do
    [ "$type" -a "$name" -a ! -e "/$1/$name" -a ! -L "/$1/$name" ] || continue
    case "$type" in
      L) ln -s $arg1 /$1/$name ;;
      D) mkdir -p /$1/$name ;;
      M) mknod -m 600 /$1/$name $arg1 ;;
      *) echo "links.conf: unparseable line ($type $name $arg1)" >&2 ;;
    esac
  done

  return $ret
}

##############################################################################

[ -x /sbin/udevd ] || exit 0

PATH="/sbin:/bin"

# defaults
tmpfs_size="2M"
udev_root="/dev"

if [ -e /etc/udev/udev.conf ]; then
  . /etc/udev/udev.conf
fi

##############################################################################

# When modifying this script, do not forget that between the time that the
# new /dev has been mounted and udevadm trigger has been run there will be
# no /dev/null. This also means that you cannot use the "&" shell command.

case "$1" in
    start)
    if [ -e "$udev_root/.udev/" ]; then
	if mountpoint -q $udev_root/; then
	    TMPFS_MOUNTED=1
	else
	    echo ".udev/ already exists on the static $udev_root!"
	fi
    fi

    echo > /sys/kernel/uevent_helper

    if [ -z "$TMPFS_MOUNTED" ]; then
	unmount_devpts
	mount_tmpfs
    else
	# and clean up the database of the initramfs udev
	rm -rf /dev/.udev/
    fi

    # /dev/null must be created before udevd is started
    if ! make_extra_nodes "$udev_root"; then
	COLDPLUG=yes
    fi
    if [ ! -f "$COLDPLUG_TARBALL" ]; then
	COLDPLUG=yes
    fi

    # if this directory is not present /dev will not be updated by udev
    mkdir -p /dev/.udev/db/

    echo "Startting the hotplug events dispatcher"
    udevd --daemon

    mkdir -p /dev/.udev/queue/ /dev/.udev/rules.d/

    create_dev_makedev

    if [ $COLDPLUG != "no" ]; then
        echo "Synthesizing the initial hotplug events"
        udevadm trigger

        # wait for the udevd childs to finish
        echo "Waiting for /dev to be fully populated"
        if udevadm settle; then
            echo 'done'
        else
            echo 'timeout'
        fi
    fi

    ;;

    stop)
    echo "Stopping the hotplug events dispatcher"
    start-stop-daemon --stop --name udevd --quiet --oknodo
    ;;

    restart)
    echo "Stopping the hotplug events dispatcher"
    start-stop-daemon --stop --name udevd --quiet --oknodo

    echo "Startting the hotplug events dispatcher"
    udevd --daemon
    ;;

    reload|force-reload)
    udevadm control --reload_rules
    ;;

    *)
    echo "Usage: /etc/init.d/udev {start|stop|restart|reload|force-reload}"
    exit 1
    ;;
esac

exit 0