File

util/timer.lua @ 12480:7e9ebdc75ce4

net: isolate LuaSec-specifics For this, various accessor functions are now provided directly on the sockets, which reach down into the LuaSec implementation to obtain the information. While this may seem of little gain at first, it hides the implementation detail of the LuaSec+LuaSocket combination that the actual socket and the TLS layer are separate objects. The net gain here is that an alternative implementation does not have to emulate that specific implementation detail and "only" has to expose LuaSec-compatible data structures on the new functions.
author Jonas Schäfer <jonas@wielicki.name>
date Wed, 27 Apr 2022 17:44:14 +0200
parent 11264:2cdcf55c6dd5
child 12975:d10957394a3c
line wrap: on
line source

-- Prosody IM
-- Copyright (C) 2008-2010 Matthew Wild
-- Copyright (C) 2008-2010 Waqas Hussain
--
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--

local indexedbheap = require "util.indexedbheap";
local log = require "util.logger".init("timer");
local server = require "net.server";
local get_time = require "util.time".now
local type = type;
local debug_traceback = debug.traceback;
local tostring = tostring;
local xpcall = require "util.xpcall".xpcall;
local math_max = math.max;
local pairs = pairs;

if server.timer then
	-- The selected net.server implements this API, so defer to that
	return server.timer;
end

local _ENV = nil;
-- luacheck: std none

local _add_task = server.add_task;

local _server_timer;
local _active_timers = 0;
local h = indexedbheap.create();
local params = {};
local next_time = nil;
local function _traceback_handler(err) log("error", "Traceback[timer]: %s", debug_traceback(tostring(err), 2)); end
local function _on_timer(now)
	local peek;
	local readd;
	while true do
		peek = h:peek();
		if peek == nil or peek > now then break; end
		local _, callback, id = h:pop();
		local param = params[id];
		params[id] = nil;
		--item(now, id, _param);
		local success, err = xpcall(callback, _traceback_handler, now, id, param);
		if success and type(err) == "number" then
			if readd then
				readd[id] = { callback, err + now };
			else
				readd = { [id] = { callback, err + now } };
			end
			params[id] = param;
		end
	end

	if readd then
		for id,timer in pairs(readd) do
			h:insert(timer[1], timer[2], id);
		end
		peek = h:peek();
	end

	if peek ~= nil and _active_timers > 1 and peek == next_time then
		-- Another instance of _on_timer already set next_time to the same value,
		-- so it should be safe to not renew this timer event
		peek = nil;
	else
		next_time = peek;
	end

	if peek then
		-- peek is the time of the next event
		return peek - now;
	end
	_active_timers = _active_timers - 1;
end
local function add_task(delay, callback, param)
	local current_time = get_time();
	local event_time = current_time + delay;

	local id = h:insert(callback, event_time);
	params[id] = param;
	if next_time == nil or event_time < next_time then
		next_time = event_time;
		if _server_timer then
			_server_timer:close();
			_server_timer = nil;
		else
			_active_timers = _active_timers + 1;
		end
		_server_timer = _add_task(next_time - current_time, _on_timer);
	end
	return id;
end
local function stop(id)
	params[id] = nil;
	local result, item, result_sync = h:remove(id);
	local peek = h:peek();
	if peek ~= next_time and _server_timer then
		next_time = peek;
		_server_timer:close();
		if next_time ~= nil then
			_server_timer = _add_task(math_max(next_time - get_time(), 0), _on_timer);
		end
	end
	return result, item, result_sync;
end
local function reschedule(id, delay)
	local current_time = get_time();
	local event_time = current_time + delay;
	h:reprioritize(id, delay);
	if next_time == nil or event_time < next_time then
		next_time = event_time;
		_add_task(next_time - current_time, _on_timer);
	end
	return id;
end

return {
	add_task = add_task;
	stop = stop;
	reschedule = reschedule;
};