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diff --git a/modules/base/luasrc/http/protocol/date.lua b/modules/base/luasrc/http/protocol/date.lua
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+++ b/modules/base/luasrc/http/protocol/date.lua
@@ -0,0 +1,115 @@
+--[[
+
+HTTP protocol implementation for LuCI - date handling
+(c) 2008 Freifunk Leipzig / Jo-Philipp Wich <xm@leipzig.freifunk.net>
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+        http://www.apache.org/licenses/LICENSE-2.0
+
+$Id$
+
+]]--
+
+--- LuCI http protocol implementation - date helper class.
+-- This class contains functions to parse, compare and format http dates.
+module("luci.http.protocol.date", package.seeall)
+
+require("luci.sys.zoneinfo")
+
+
+MONTHS = {
+	"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug",
+	"Sep", "Oct", "Nov", "Dec"
+}
+
+--- Return the time offset in seconds between the UTC and given time zone.
+-- @param tz	Symbolic or numeric timezone specifier
+-- @return		Time offset to UTC in seconds
+function tz_offset(tz)
+
+	if type(tz) == "string" then
+
+		-- check for a numeric identifier
+		local s, v = tz:match("([%+%-])([0-9]+)")
+		if s == '+' then s = 1 else s = -1 end
+		if v then v = tonumber(v) end
+
+		if s and v then
+			return s * 60 * ( math.floor( v / 100 ) * 60 + ( v % 100 ) )
+
+		-- lookup symbolic tz
+		elseif luci.sys.zoneinfo.OFFSET[tz:lower()] then
+			return luci.sys.zoneinfo.OFFSET[tz:lower()]
+		end
+
+	end
+
+	-- bad luck
+	return 0
+end
+
+--- Parse given HTTP date string and convert it to unix epoch time.
+-- @param data	String containing the date
+-- @return		Unix epoch time
+function to_unix(date)
+
+	local wd, day, mon, yr, hr, min, sec, tz = date:match(
+		"([A-Z][a-z][a-z]), ([0-9]+) " ..
+		"([A-Z][a-z][a-z]) ([0-9]+) " ..
+		"([0-9]+):([0-9]+):([0-9]+) " ..
+		"([A-Z0-9%+%-]+)"
+	)
+
+	if day and mon and yr and hr and min and sec then
+		-- find month
+		local month = 1
+		for i = 1, 12 do
+			if MONTHS[i] == mon then
+				month = i
+				break
+			end
+		end
+
+		-- convert to epoch time
+		return tz_offset(tz) + os.time( {
+			year  = yr,
+			month = month,
+			day   = day,
+			hour  = hr,
+			min   = min,
+			sec   = sec
+		} )
+	end
+
+	return 0
+end
+
+--- Convert the given unix epoch time to valid HTTP date string.
+-- @param time	Unix epoch time
+-- @return		String containing the formatted date
+function to_http(time)
+	return os.date( "%a, %d %b %Y %H:%M:%S GMT", time )
+end
+
+--- Compare two dates which can either be unix epoch times or HTTP date strings.
+-- @param d1	The first date or epoch time to compare
+-- @param d2	The first date or epoch time to compare
+-- @return		-1  -  if d1 is lower then d2
+-- @return		0   -  if both dates are equal
+-- @return		1   -  if d1 is higher then d2
+function compare(d1, d2)
+
+	if d1:match("[^0-9]") then d1 = to_unix(d1) end
+	if d2:match("[^0-9]") then d2 = to_unix(d2) end
+
+	if d1 == d2 then
+		return 0
+	elseif d1 < d2 then
+		return -1
+	else
+		return 1
+	end
+end