File

util/watchdog.lua @ 10799:763bb2ce3f60

util.pposix,signal: Pass around various OS numbers as integers [Lua 5.3] Passing around PIDs, UIDs etc as integers makes it more sane in Lua 5.3. Getting 1234.0 as PID is silly. Shouldn't change any behavior as these are all integers on the C side and the integral floats are accepted as integers when passed back from Lua into C.
author Kim Alvefur <zash@zash.se>
date Mon, 04 May 2020 21:51:30 +0200
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;
};