[packages] olsrd: init: parse new var 'speed', which translates to several other vars

Range is 1...20 where 1 is fastest protocol speed and 20 is the slowest protocol speed

Like in the Freifunk-Firmware from sven-ola we accept now a per-interface
option 'speed', which should range from 1...20 and is sanitized. when the
value is not in valid range, it defaults to 6 which allows the daemon to
start and behave like in a city-wide mesh. (same default like in freifunk firmware)

The value 'speed' overrides the normal values for emission intervals like
Hello-, Tc-, Mid-, Hna-Interval/ValidityTime or sets them explicitely. this
makes it much easier to play with intervals on several routers:

Instead of changes eight values, we only have to alter 1 value.

The value-calculation is tested since several years.
Signed-off-by: NBastian Bittorf <bittorf@bluebottle.com>

git-svn-id: svn://svn.openwrt.org/openwrt/packages/net/olsrd@36299 3c298f89-4303-0410-b956-a3cf2f4a3e73

files/olsrd.init

@@ -225,6 +225,7 @@ config_update_schema() {
 }
 
 config_write_options() {
+	local funcname="config_write_options"
 	unset IFS
 	local schema="$1"
 	local cfg="$2"
@@ -244,6 +245,8 @@ config_write_options() {
 	local list_value
 	local i
 	local position
+	local speed
+	local list_speed_vars="HelloInterval HelloValidityTime TcInterval TcValidityTime MidInterval MidValidityTime HnaInterval HnaValidityTime"
 
 	get_value_for_entry()
 	{
@@ -262,12 +265,90 @@ config_write_options() {
 		[ "$option_type" = internal ] && return 1
 
 		config_get value "$cfg" "$option"
+		[ "$option" = "speed" ] && return 1
 
 		return 0
 	}
 
+	case " $schema " in
+		*" speed "*)
+			get_value_for_entry "speed"
+
+			if [ 2>/dev/null $value -gt 0 -a $value -le 20 ]; then
+				speed="$value"
+			else
+				log "$funcname() Warning: invalid speed-value: '$value' - allowed integers: 1...20, fallback to 6"
+				speed=6
+			fi
+
+			already_in_schema()
+			{
+				case " $schema " in
+					*" $1 "*)
+						return 0
+					;;
+					*)
+						return 1
+					;;
+				esac
+			}
+
+			for schema_entry in $list_speed_vars; do {
+				already_in_schema "$schema_entry" || schema="$schema $schema_entry"
+			} done
+		;;
+	esac
+
 	for schema_entry in $schema; do
-		get_value_for_entry "$schema_entry" || continue
+		if [ -n "$speed" ]; then		# like sven-ola freifunk firmware fff-1.7.4
+			case "$schema_entry" in
+				HelloInterval)
+					value="$(( $speed / 2 + 1 )).0"
+				;;
+				HelloValidityTime)
+					value="$(( $speed * 25 )).0"
+				;;
+				TcInterval)	# todo: not fisheye? -> $(( $speed * 2 ))
+					value=$(( $speed / 2 ))
+					[ $value -eq 0 ] && value=1
+					value="$value.0"
+				;;
+				TcValidityTime)
+					value="$(( $speed * 100 )).0"
+				;;
+				MidInterval)
+					value="$(( $speed * 5 )).0"
+				;;
+				MidValidityTime)
+					value="$(( $speed * 100 )).0"
+				;;
+				HnaInterval)
+					value="$(( $speed * 2 )).0"
+				;;
+				HnaValidityTime)
+					value="$(( $speed * 25 )).0"
+				;;
+				*)
+					get_value_for_entry "$schema_entry" || continue
+				;;
+			esac
+
+			is_speed_var()
+			{
+				case " $list_speed_vars " in
+					*" $1 "*)
+						return 0
+					;;
+					*)
+						return 1
+					;;
+				esac
+			}
+
+			is_speed_var "$schema_entry" && option="$schema_entry"
+		else
+			get_value_for_entry "$schema_entry" || continue
+		fi
 
 		if [ -z "$value" ]; then
 			IFS='+'