mod_posix: Move POSIX signal handling into util.startup to avoid race When libunbound is initialized, it spawns a thread to work in. In case a module initializes libunbound, e.g. by triggering a s2s connection, Prosody would not handle signals, instead immediately quit on e.g. the reload (SIGHUP) signal. Likely because the libunbound thread would not have inherited the signal mask from the main Prosody thread. Thanks Menel, riau and franck-x for reporting and help narrowing down

-- 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;
end

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

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