#! /bin/sh
#
# /usr/sbin/dahdi_span_types
#
# This script can be used both from udev and
# from the command line to manage PRI spans
# type (E1/T1/J1).
#
# Span types can be set only *BEFORE* span are assigned.
#
# It uses a configuration file: $DAHDICONFDIR/span-types.conf
# (default DAHDICONFDIR=/etc/dahdi)
# (the format is documented inside that file)
#
# The first argument is an action:
#   "set"        - actually write the setting to the driver
#   "list"       - human-readable list of E1/T1/J1 types
#   "dumpconfig" - dump current assignments in a /etc/dahdi/span-types.conf
#                  compatible format
#
# Without further arguments, it operates on all existing spans
# With one or more sysfs dahdi_devices it is limited to those.
#
# We may use alternative "keys" for device matching:
# * Available keys:
#   - "hwid"       - Hardware id attribute from sysfs
#   - "@location"  - Location attribute from sysfs (embeded inside '<>')
#   - "/devpath"   - The sysfs absolute devpath
#
# * Wildcard are allowed in the configuration file:
#   - In the device specifiers (keys)
#   - In the span numbers
#   - Example for "match-all":    *   *:T1
#
# * During "set":
#   - If there are multiple matches, for a span, all are applied
#   - They are always applied in their order in the configuration file
#   - This means the last match wins
#   - Example:
#         *                   *:T1        # All span on all devices are T1
#         usb:X1234567        [34]:E1	   # Except spans 3,4 on specific device
#
# * During "dumpconfig", for each device we take the first available key:
#   - The preference is: "hwid" or else "@location" or else "/devpath"
#   - This can be overriden via the SPAN_ASSIGNMENTS_KEY environment variable
#     or the '{-k|--key} key' command line option.
#
# Command line options:
#  - The '-h|--help' show a usage message.
#  - The '-v|--verbose' show debugging messages (on stderr)
#  - The '-n|--dry-run' During "set", only show what would be done
#  - The '-k <key>|--key <key>' overrides the SPAN_ASSIGNMENTS_KEY environment
#    variable.
#
# Examples:
#    dahdi_span_types list
#    dahdi_span_types set	     # all devices
#    dahdi_span_types set /sys/bus/dahdi_devices/devices/astribanks:xbus-00
#    dahdi_span_types -k location dumpconfig
#


devbase='/sys/bus/dahdi_devices/devices'
DAHDICONFDIR="${DAHDICONFDIR:-/etc/dahdi}"
DAHDISPANTYPESCONF="${DAHDISPANTYPESCONF:-"${DAHDICONFDIR}/span-types.conf"}"
SPAN_ASSIGNMENTS_KEY=${SPAN_ASSIGNMENTS_KEY:-hwid}

usage() {
	echo >&2 "Usage: $0 [options] action [devpath ...]"
	echo >&2 "       action:"
	echo >&2 "         set        - set spans to E1/T1 according to /etc/dahdi/span-types.conf"
	echo >&2 "         compare    - show config values that differ from system"
	echo >&2 "         list       - human-readable list of all spans"
	echo >&2 "         dumpconfig - dump current state in /etc/dahdi/span-types.conf format"
	echo >&2 ""
	echo >&2 "       options:"
	echo >&2 "         -h|--help      - Show this help"
	echo >&2 "         -v|--verbose'  - Show debugging messages (on stderr)"
	echo >&2 "         -n|--dry-run'  - During 'set', only show what would be done"
	echo >&2 "         -k|--key <k>   - Override prefered key during dumpconfig action"
	echo >&2 "         --line-mode <m> - Set default line mode to <m> (E1/T1/J1)"
	exit 1
}

# Parse command line options
TEMP=`getopt -o hnvk: --long help,dry-run,verbose,key:,line-mode: -n "$0" -- "$@"`
if [ $? != 0 ]; then
	echo >&2 "Bad options"
	usage
fi

compare=false

# Note the quotes around `$TEMP': they are essential!
eval set -- "$TEMP"

while true ; do
	case "$1" in
	-h|--help)
		usage
		;;
	-n|--dry-run)
		shift
		dry_run=true
		;;
	-v|--verbose)
		shift
		verbose=true
		;;
	-k|--key)
		SPAN_ASSIGNMENTS_KEY="$2"
		shift
		shift
		;;
	--line-mode)
		DEFAULT_LINE_MODE="$2"
		shift
		shift
		;;
	--)
		shift
		break
		;;
	*)
		echo "Internal error!"
		exit 1
		;;
	esac
done

if [ "$#" -eq 0 ]; then
	echo >&2 "Missing action argument"
	usage
fi
action="$1"
shift

# Validate SPAN_ASSIGNMENTS_KEY
case "$SPAN_ASSIGNMENTS_KEY" in
hwid|location|devpath)
	;;
*)
	echo >&2 "Bad --key='$SPAN_ASSIGNMENTS_KEY' (should be: hwid|location|devpath)"
	usage
	;;
esac

# Validate DEFAULT_LINE_MODE
case "$DEFAULT_LINE_MODE" in
E1|T1|J1|'')
	;;
*)
	echo >&2 "Bad --line-mode='$DEFAULT_LINE_MODE' (should be: E1|T1|J1)"
	usage
	;;
esac

if [ ! -d "$devbase" ]; then
	echo >&2 "$0: Missing '$devbase' (DAHDI driver unloaded?)"
	exit 1
fi

# Use given devices or otherwise, all existing devices
if [ "$#" -gt 0 ]; then
	DEVICES="$@"
else
	DEVICES=`ls -d $devbase/* 2>/dev/null`
fi

# Beware of special characters in attributes
attr_clean() {
	cat "$1" 2>/dev/null | tr -d '\n' | tr '!' '/' | tr -c 'a-zA-Z0-9/:.-' '_'
}

show_spantypes() {
	echo "# PRI span types (E1/T1/J1)"
	for device in $DEVICES
	do
		devpath=`cd "$device" && pwd -P`
		location='@'`attr_clean "$device/location"`
		hardware_id=`attr_clean "$device/hardware_id"`
		cat "$device/spantype" | while read st; do
			case "$st" in
			*:[ETJ]1)
				printf "%-10s %-20s %-30s %s\n" \
					"$st" "[$hardware_id]" "$location" \
					"$devpath"
				;;
			esac
		done
	done
}

list_pri_spantypes() {
	find $DEVICES -follow -maxdepth 1 -name spantype | \
		xargs cat | \
		sed -n '/:[ETJ]1$/s/^.*://p' | \
		sort -u | \
		tr '\n' ' ' | \
		sed -e 's/^ *//' -e 's/ *$//'
}

dump_config() {
	pri_spantypes=`list_pri_spantypes`
	num_spantypes=`echo "$pri_spantypes" | wc -w`
	gen_default=''
	echo '#'
	echo "# Autogenerated by $0 on `date`"
	echo "# Map PRI DAHDI devices to span types for E1/T1/J1"
	echo "#"

	echo "# Summary:"
	if [ "$DEFAULT_LINE_MODE" != '' ]; then
		gen_default="$DEFAULT_LINE_MODE"
		echo "#  * Generating wildcard match of $gen_default."
		echo "#    - Was run with '--line-mode=$DEFAULT_LINE_MODE'"
	elif [ "$num_spantypes" -eq 1 ]; then
		gen_default="$pri_spantypes"
		echo "#  * Generating wildcard match of $gen_default."
		echo "#    - Spans were $pri_spantypes"
	else
		echo "#  * Not generating wildcard match."
		echo "#    - Was run without '--line-mode' option and span were of mixed types [$pri_spantypes]"
	fi
	echo "#"
	if [ "$num_spantypes" -eq 1 ]; then
		echo "#  * Generating a list of commented out configurations for spans."
		echo "#    - Spans were $pri_spantypes"
		echo "#    - Uncomment for specific overrides"
	else
		echo "#  * Generating a list of specific span configurations."
		echo "#    - Spans were of mixed types: $pri_spantypes"
	fi
	echo "#"
	echo ''

	fmt="%-65s %s"
	printf "$fmt\n" '# @location/hardware_id' 'span_type'

	if [ "$gen_default" != '' ]; then
		printf "$fmt\t\t# Wildcard line-mode" "*" "*:$gen_default"
		echo ""
	fi
	echo ""
	for device in $DEVICES
	do
		devpath=`cd "$device" && pwd -P`
		location=`attr_clean "$device/location"`
		hardware_id=`attr_clean "$device/hardware_id"`
		if [ "$SPAN_ASSIGNMENTS_KEY" = 'hwid' -a "$hardware_id" != '' ]; then
			id="$hardware_id"
		elif [ "$SPAN_ASSIGNMENTS_KEY" = 'location' -a "$location" != '' ]; then
			id="@$location"
		else
			id="$devpath"
		fi
		echo "# Device: [$hardware_id] @$location $devpath"
		cat "$device/spantype" | while read st; do
			case "$st" in
			*:[ETJ]1)
				if [ "$num_spantypes" -eq 1 ]; then
					printf "#$fmt\n" "$id" "$st"
				else
					printf "$fmt\n" "$id" "$st"
				fi
				;;
			*)
				#echo "#    Skipped local span `echo $st | sed 's/:/ -- /'`"
				;;
			esac
		done | sort -n
		echo ''
	done
}

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

handle_span() {
	device="$1"
	spantype="$2"
	attr_file="$device/spantype"
	devpath=`cd "$device" && pwd -P`
	devname=`echo "$device" | sed "s,$devbase/,,"`
	location='@'`attr_clean "$device/location"`
	hardware_id=`attr_clean "$device/hardware_id"`
	spanno=`echo "$spantype" | cut -d: -f1`
	#echo >&2 "DEBUG: $device $spanno ($spantype)"
	filter_conf | while read id span_spec; do
			sn=`echo "$span_spec" | cut -d: -f1`
			val=`echo "$span_spec" | cut -d: -f2`
			case "$spanno" in
			$sn)
				;;
			*)
				#echo >&2 "no-match($device $spanno): $sn"
				continue
				;;
			esac
			found=no
			# GLOBBING
			case "$location" in
			$id)
				#echo >&2 "match($id): $span_spec"
				found=yes
				;;
			esac
			case "$hardware_id" in
			$id)
				#echo >&2 "match([$id]): $span_spec"
				found=yes
				;;
			esac
			case "$devpath" in
			$id)
				#echo >&2 "match([$id]): $span_spec"
				found=yes
				;;
			esac
			if [ "$found" = 'yes' ]; then
				if [ "$dry_run" = 'true' -o "$verbose" = 'true' ]; then
					echo >&2 "Set $devname span $spanno = $val"
				fi
				if [ "$dry_run" != 'true' ]; then
					if [ "$compare" = 'true' ]; then
						config="$spanno:$val"
						system=`grep "$spanno:" "$attr_file"`
						if [ "$config" != "$system" ]; then

							active_val=`echo $system | cut -d: -f2`
							echo "$devname $spanno     $val     $active_val" >>"$compare_results_file"
						fi
					else
						echo "$spanno:$val" > "$attr_file"
					fi
				fi
			fi
		done
}

set_all_devices() {
	span_differs='false'
	SPANS_DIFFER='false'

	if [ ! -f "$DAHDISPANTYPESCONF" ]; then
		echo >&2 "$0: Missing configuration '$DAHDISPANTYPESCONF'"
		exit 1
	fi
	for device in $DEVICES
	do
		devname=`echo "$device" | sed "s,$devbase/,,"`
		cat "$device/spantype" | while read spantype; do
			case "$spantype" in
			*:[ETJ]1)
				handle_span "$device" "$spantype"
				;;
			*)
				if [ "$dry_run" = 'true' -o "$verbose" = 'true' ]; then
					echo >&2 "Skipping non-E1/T1/J1 span ($devname -- $spantype)"
				fi
				;;
			esac
		done
	done
	if [ "$compare" = 'true' ]; then
		if [ -s "$compare_results_file" ]; then
			echo "# Device           Unit  Config Active"
			cat "$compare_results_file"
			rm -f "$compare_results_file"
			exit 5
		fi
		rm -f "$compare_results_file"
		exit 0
	fi
}

case "$action" in
list)
	show_spantypes
	;;
dumpconfig)
	dump_config
	;;
set)
	set_all_devices
	;;
compare)
	compare=true
	compare_results_file=`mktemp`
	set_all_devices
	;;
*)
	usage
	;;
esac