util/watchdog.lua
author Jonas Schäfer <jonas@wielicki.name>
Sat, 15 Jan 2022 15:40:29 +0100
changeset 12193 82c8e855c850
parent 8558 4f0f5b49bb03
child 12549 5059a639f61e
permissions -rw-r--r--
mod_storage_xep0227: treat roster metadata pseudo-entry correctly The roster version is stored in a pseudo-item which has the key `false`. The if condition in the touched code attempts to guard against this, but it does not take into account that the jid prepping returns nil instead of false. By moving the jid prepping into the if, we can check for the metadata entry safely.

local timer = require "util.timer";
local setmetatable = setmetatable;
local os_time = os.time;

local _ENV = nil;
-- luacheck: std none

local watchdog_methods = {};
local watchdog_mt = { __index = watchdog_methods };

local function new(timeout, callback)
	local watchdog = setmetatable({ timeout = timeout, last_reset = os_time(), callback = callback }, watchdog_mt);
	timer.add_task(timeout+1, function (current_time)
		local last_reset = watchdog.last_reset;
		if not last_reset then
			return;
		end
		local time_left = (last_reset + timeout) - current_time;
		if time_left < 0 then
			return watchdog:callback();
		end
		return time_left + 1;
	end);
	return watchdog;
end

function watchdog_methods:reset()
	self.last_reset = os_time();
end

function watchdog_methods:cancel()
	self.last_reset = nil;
end

return {
	new = new;
};