File

util/hex.lua @ 9307:feaef6215bb8

util.stanza: Don't automatically generate ids for iq stanzas Users of this API should provide their own id attribute that meets their uniqueness requirements. The current implementation leaks information (i.e. how many iq stanzas have been sent by the server to other JIDs). Providing any strong guarantees of randomness here would need to pull in additional dependencies that we don't want in this simple library.
author Matthew Wild <mwild1@gmail.com>
date Thu, 13 Sep 2018 16:35:48 +0100
parent 6802:442019e955dc
child 12355:a0ff5c438e9d
line wrap: on
line source

local s_char = string.char;
local s_format = string.format;
local s_gsub = string.gsub;
local s_lower = string.lower;

local char_to_hex = {};
local hex_to_char = {};

do
	local char, hex;
	for i = 0,255 do
		char, hex = s_char(i), s_format("%02x", i);
		char_to_hex[char] = hex;
		hex_to_char[hex] = char;
	end
end

local function to(s)
	return (s_gsub(s, ".", char_to_hex));
end

local function from(s)
	return (s_gsub(s_lower(s), "%X*(%x%x)%X*", hex_to_char));
end

return { to = to, from = from }