# starts udev
# $Header$

seed_dev()
{
	echo -e ${COLOREDSTAR}"  Seeding /dev with needed nodes ..."

	# not provided by sysfs but needed
	ln -snf /proc/self/fd /dev/fd
	ln -snf fd/0 /dev/stdin
	ln -snf fd/1 /dev/stdout
	ln -snf fd/2 /dev/stderr
	ln -snf /proc/kcore /dev/core
	ln -snf /proc/asound/oss/sndstat /dev/sndstat

	# create problematic directories
	mkdir -p /dev/{pts,shm}

	return 0
}

# some needed functions functions
populate_udev()
{
	# trigger via uevents on newer kernels (>= 2.6.15)
	if [ "$(kernel_version | sed 's:\.::g')" -gt "2614" ]
	then
		echo -e ${COLOREDSTAR}"  Populating /dev with existing devices through uevents ..."
		trigger_uevents
		evaluate_retval
	else
		echo -e ${COLOREDSTAR}"  Populating /dev with existing devices via udevstart ..."
		/sbin/udevstart
		evaluate_retval
	fi

	# loop until everything is finished
	# there's gotta be a better way...
	echo -e ${COLOREDSTAR}"  Letting udev process events ..."
	local loop=0
	while test -d /dev/.udev/queue
	do
		sleep 0.1;
		test "${loop}" -gt 300 && break
		loop=$((${loop} + 1))
	done
	evaluate_retval

	return 0
}

# This works for 2.6.15 kernels or greater
trigger_uevents()
{
	local list=""
	local i
	local first
	local last
	local default

	# if you want real coldplug (with all modules being loaded for all
	# devices in the system), uncomment out the next line.
	#list="${lis}t $(echo /sys/bus/*/devices/*/uevent)"
	list="${list} $(echo /sys/class/*/*/uevent)"
	list="${list} $(echo /sys/block/*/uevent /sys/block/*/*/uevent)"
	for i in ${list}
	do
		case "${i}" in
			*/device/uevent)
				# skip followed device symlinks
				continue
				;;
			*/class/mem/*|*/class/tty/*)
				first="${first} ${i}"
				;;
			*/block/md*)
				last="${last} ${i}"
				;;
			*/*)
				default="${default} ${i}"
				;;
		esac
	done

	# trigger the sorted events
	for i in ${first} ${default} ${last}
	do
		echo "add" > "${i}"
	done
}

start_udev()
{

        # create a ramdisk for populating udev
        echo -e ${COLOREDSTAR}"Mounting udev at /dev ..."
        # many video drivers needed exec access
        fstype=ramfs
        # tmpfs was suggested by Greg Kroah-Hartman
        kernel_supports_fs tmpfs && fstype=tmpfs
        # mount devtmpfs if supported
        kernel_supports_fs devtmpfs && fstype=devtmpfs
        mount -n -t ${fstype} udev /dev -o exec,nosuid,mode=0755,size=10M
        evaluate_retval

	# if a device tarball exists load it and if it is activated
	echo -e ${COLOREDSTAR}"Configurating system to use udev ..."
	if [[ ${RC_DEVICE_TARBALL} = yes ]]
	then
		echo -e ${COLOREDSTAR}"  Populating /dev with with device nodes ..."
		tar -jxpf /lib/udev-state/devices.tar.bz2 -C /dev
		evaluate_retval
	fi

	seed_dev

	# use netlink to manage udev with newer kernels
	if [ "$(kernel_version | sed 's:\.::g')" -gt "2614" ]
	then
		echo -e ${COLOREDSTAR}"  Using netlink for hotplug events ..."
		echo "" > /proc/sys/kernel/hotplug

	elif [ -e /proc/sys/kernel/hotplug ]
	then
		echo -e ${COLOREDSTAR}"  Setting /sbin/udev as hotplug agent ..."
		echo "/sbin/udev" > /proc/sys/kernel/hotplug
	else
		echo -e ${COLOREDSTAR}${COLYELLOW}"  Kernel was not compiled with hotplug support !"
	fi
	evaluate_retval

	# start udev daemon
        echo -e ${COLOREDSTAR}"  Starting udevd daemon ..."
	start-stop-daemon --start --exec /sbin/udevd -- --daemon
        evaluate_retval

	# now load udev
	populate_udev
}

stop_udev()
{
        echo -e ${COLOREDSTAR}"  Stopping udevd daemon ..."
        start-stop-daemon --stop --exec /sbin/udevd
        evaluate_retval

	# if requested save devices to a device tarball before halt
	# only for kernels >=2.6 *and* udev
	# make sure that udev is mounted but *not* devfs --> /dev/.devfsd
	if [[ ${RC_DEVICE_TARBALL} = yes ]] && \
		[ -e /dev/.udev -a ! -e /dev/.devfsd -a ! -e /.bootdev ]
	then
		echo -e ${COLOREDSTAR}"Saving /dev device nodes ..."
		( cd /dev; tar -jclpf "/tmp/devices-$$.tar.bz2" * &> /dev/null )
		mv -f "/tmp/devices-$$.tar.bz2" /lib/udev-state/devices.tar.bz2
		evaluate_retval
	fi
}

start_devicemanager()
{
	start_udev
}

stop_devicemanager()
{
	stop_udev
}