File

util/watchdog.lua @ 11961:542a9a503073

util.async: Add sleep() method with configurable scheduling backend No scheduler set by default, so it will error (we plan to initialize it in util.startup). We wanted to avoid a hard dependency on util.timer (which in turn depends on network backends, etc.), and we didn't add timer.sleep() because we didn't want to add a hard dependency on util.async for things that don't need it.
author Matthew Wild <mwild1@gmail.com>
date Mon, 29 Nov 2021 14:11:24 +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;
};