File

util/bitcompat.lua @ 12115:94de6b7596cc

mod_tombstones: Remember deleted accounts #1307 Presence subscriptions are normally revoked on account deletion, which informs the contact. Sometimes this notification gets lost e.g. due to s2s problems. The accounts JID may also be present e.g. in MUC affiliations, chat group member lists, pubsub subscriptions or other systems. These may grant privileges which would fall to someone who creates the same account again, which this module is meant to prevent.
author Kim Alvefur <zash@zash.se>
date Thu, 23 Dec 2021 14:08:20 +0100
parent 10241:48f7cda4174d
child 12573:0f4feaf9ca64
line wrap: on
line source

-- Compatibility layer for bitwise operations

-- First try the bit32 lib
-- Lua 5.3 has it with compat enabled
-- Lua 5.2 has it by default
if _G.bit32 then
	return _G.bit32;
else
	-- Lua 5.1 may have it as a standalone module that can be installed
	local ok, bitop = pcall(require, "bit32")
	if ok then
		return bitop;
	end
end

do
	-- Lua 5.3 and 5.4 would be able to use native infix operators
	local ok, bitop = pcall(require, "util.bit53")
	if ok then
		return bitop;
	end
end

do
	-- Lastly, try the LuaJIT bitop library
	local ok, bitop = pcall(require, "bit")
	if ok then
		return bitop;
	end
end

error "No bit module found. See https://prosody.im/doc/depends#bitop";