-- querystring and post body parsing

local function urldecode(s)
	return s:gsub('+',' ')
		:gsub('%%(%x%x)',function(x)
			return string.char(tonumber(x,16))
		end)
end

local function parse_qs(s)
	local ix = 1
	local res = {}
	while true do
		local _,next_ix,ek,ev = s:find("([^=]+)=([^&]*)&?",ix)
		if not ek then break end
		local k,v = urldecode(ek), urldecode(ev)
		res[k] = v
		ix = next_ix + 1
	end
	return res
end