File

util/watchdog.lua @ 11962:9a70a543c727

util.async: Add next-tick configuration Running woken runners in the next iteration of the event loop prevents unexpected recursion, unexpected tracebacks, and is generally more predictable. The pattern is borrowed from util.promise, where we're now doing the same.
author Matthew Wild <mwild1@gmail.com>
date Mon, 29 Nov 2021 14:14:30 +0000
parent 8555:4f0f5b49bb03
child 12545:5059a639f61e
line wrap: on
line source

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;
};