File

util/uuid.lua @ 12630:781772c8b6d9

mod_mam: Store archives with sub-second precision timestamps Changes sub-second part of example timestamp to .5 in order to avoid floating point issues. Some clients use timestamps when ordering messages which can lead to messages having the same timestamp ending up in the wrong order. It would be better to preserve the order messages are sent in, which is the order they were stored in.
author Kim Alvefur <zash@zash.se>
date Sun, 14 Aug 2022 17:28:31 +0200
parent 12355:a0ff5c438e9d
child 12975:d10957394a3c
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-- Prosody IM
-- Copyright (C) 2008-2010 Matthew Wild
-- Copyright (C) 2008-2010 Waqas Hussain
--
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--

local random = require "util.random";
local random_bytes = random.bytes;
local hex = require "util.hex".encode;
local m_ceil = math.ceil;

local function get_nibbles(n)
	return hex(random_bytes(m_ceil(n/2))):sub(1, n);
end

local function get_twobits()
	return ("%x"):format(random_bytes(1):byte() % 4 + 8);
end

local function generate()
	-- generate RFC 4122 complaint UUIDs (version 4 - random)
	return get_nibbles(8).."-"..get_nibbles(4).."-4"..get_nibbles(3).."-"..(get_twobits())..get_nibbles(3).."-"..get_nibbles(12);
end

return {
	get_nibbles=get_nibbles;
	generate = generate ;
	-- COMPAT
	seed = random.seed;
};