working lua impl. of base64

lua_modules/base64/base64_v2.lua

@@ -0,0 +1,35 @@
+--this version actually works
+
+local tab = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
+base64 = {
+	enc = function(data)
+		local l,out = 0,''
+		local d = data..string.rep('\0',(3-data:len()%3)%3)
+		for i=1,d:len() do
+			l = bit.lshift(l,8)
+			l = l+d:byte(i,i)
+			if i%3==0 then
+				while l > 0 do
+					local a = bit.rshift(l,18)+1
+					out = out..tab:sub(a,a)
+					l = bit.band(bit.lshift(l,6),0xFFFFFF)
+				end
+			end
+		end
+		return out..({'','==','='})[data:len()%3+1]
+	end,
+	dec = function(data)
+		local a,b = data:gsub('=','A')
+		local out = ''
+		local l = 0
+		for i=1,a:len() do
+			l=l+tab:find(a:sub(i,i))-1
+			if i%4==0 then 
+				out=out..string.char(bit.rshift(l,16),bit.band(bit.rshift(l,8),255),bit.band(l,255))
+				l=0
+			end
+			l=bit.lshift(l,6)
+		end
+		return out:sub(1,-b-1)
+	end
+}