#! /bin/sh
#
# /usr/share/dahdi/span_types:
#
# this script can be used both from udev and
# from the command line for spantype management.
#
# It use a configuration file /etc/dahdi/spantype.conf
# (the format is documented inside this file)
#
# The first argument is an action:
#   "list" to show existing E1/T1/J1 types
#   "dump" the same, but in a format (almost) suitable for
#          the configuration file
#          FIXME: we currently don't have the base channo in sysfs.
#   "set"  actually write the setting to the driver
#
# Examples:
#    span_types list
#    span_types dump
#    span_types set	# all
#    span_types set /sys/bus/dahdi_devices/devices/astribanks:xbus-00
#


devbase='/sys/bus/dahdi_devices/devices'
DAHDICONFDIR="${DAHDICONFDIR:-/etc/dahdi}"
spantype_conf="$DAHDICONFDIR/spantype.conf"

usage() {
	echo >&2 "Usage: $0 {list|dump|set} [devpath ...]"
	exit 1
}

if [ "$#" -eq 0 ]; then
	usage
fi
action="$1"
shift

# Use given devices or otherwise, all existing devices
if [ "$#" -gt 0 ]; then
	DEVICES="$@"
else
	DEVICES=`echo $devbase/*`
fi

show_spantypes() {
	for device in $DEVICES
	do
		hw_id=`cat "$device/hardware_id"`
		location='@'`cd "$device" && pwd -P | sed 's,/sys/devices/,,'`
		cat "$device/spantype" | while read st; do
			printf "%-10s %-20s %s\n" "$st" "[$hw_id]" "$location"
		done | sort -n
	done
}

dump_config() {
	fmt="%-65s %s\n"
	echo "# Map of dahdi_devices to span types for E1/T1/J1"
	printf "$fmt" '# @location/hardware_id' 'span_type'
	for device in $DEVICES
	do
		hw_id=`cat "$device/hardware_id"`
		location='@'`cd "$device" && pwd -P | sed 's,/sys/devices/,,'`
		if [ -n "$hw_id" ]; then
			id="$hw_id"
		else
			id="$location"
		fi
		cat "$device/spantype" | while read st; do
			case "$st" in
			*:[ETJ]1)
				printf "$fmt" "$id" "$st"
				;;
			esac
		done | sort -n
	done
}

# Allow comments and empty lines in config file
filter_conf() {
	sed -e 's/#.*//' -e '/^[ \t]*$/d' "$spantype_conf"
}

conf_spans() {
	hw_id="$1"
	location="$2"
	filter_conf | (
		# Collect device spans
		# in a subshell, so $SPANS is not lost
		SPANS=''
		while read id spans; do
			# GLOBBING
			case "$location" in
			$id)
				#echo >&2 "match($id): $spans"
				SPANS="$SPANS $spans"
				;;
			esac
			case "$hw_id" in
			$id)
				#echo >&2 "match([$id]): $spans"
				SPANS="$SPANS $spans"
				;;
			esac
		done
		echo "$SPANS"
	)
}

# Beware of special characters in attributes
attr_clean() {
	cat "$1" | tr -d '\n' | tr '!' '/' | tr -c 'a-zA-Z0-9/:.-' '_'
}

device_set_spantype() {
	device="$1"
	attr_file="$device/spantype"
	hw_id=`attr_clean "$device/hardware_id"`
	location='@'`cd "$device" && pwd -P | sed 's,/sys/devices/,,'`
	spanspecs=`conf_spans "$hw_id" "$location"`
	echo >&2 "MATCHED($device): $spanspecs"
	cut -d: -f1 "$attr_file" | while read spanno; do
			for sp in $spanspecs
			do
				s=`echo "$sp" | cut -d: -f1`
				v=`echo "$sp" | cut -d: -f2`
				case "$spanno" in
				$s)
					#echo >&2 "conf($attr_file): $spanno:$v"
					echo "$spanno:$v" > "$attr_file"
					;;
				esac
			done
		done
}

set_spantypes() {
	for device in $DEVICES
	do
		device_set_spantype "$device"
	done
}

case "$action" in
list)
	show_spantypes
	;;
dump)
	dump_config
	;;
set)
	set_spantypes
	;;
*)
	usage
	;;
esac