File

plugins/mod_scansion_record.lua @ 11665:148075532021

net.server_epoll: Prevent stack overflow of opportunistic writes net.http.files serving a big enough file on a fast enough connection with opportunistic_writes enabled could trigger a stack overflow through repeatedly serving more data that immediately gets sent, draining the buffer and triggering more data to be sent. This also blocked the server on a single task until completion or an error. This change prevents nested opportunistic writes, which should prevent the stack overflow, at the cost of reduced download speed, but this is unlikely to be noticeable outside of Gbit networks. Speed at the cost of blocking other processing is not worth it, especially with the risk of stack overflow.
author Kim Alvefur <zash@zash.se>
date Sun, 11 Jul 2021 09:39:21 +0200
parent 11254:613035d6e5a0
child 12110:b5b799a2a10c
line wrap: on
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local names = { "Romeo", "Juliet", "Mercutio", "Tybalt", "Benvolio" };
local devices = { "", "phone", "laptop", "tablet", "toaster", "fridge", "shoe" };
local users = {};

local filters = require "util.filters";
local id = require "util.id";
local dt = require "util.datetime";
local dm = require "util.datamanager";
local st = require "util.stanza";

local record_id = id.medium():lower();
local record_date = os.date("%Y%b%d"):lower();
local header_file = dm.getpath(record_id, "scansion", record_date, "scs", true);
local record_file = dm.getpath(record_id, "scansion", record_date, "log", true);

local head = io.open(header_file, "w");
local scan = io.open(record_file, "w+");

local function record(string)
	scan:write(string);
	scan:flush();
end

local function record_header(string)
	head:write(string);
	head:flush();
end

local function record_object(class, name, props)
	head:write(("[%s] %s\n"):format(class, name));
	for k,v in pairs(props) do
		head:write(("\t%s: %s\n"):format(k, v));
	end
	head:write("\n");
	head:flush();
end

local function record_event(session, event)
	record(session.scansion_id.." "..event.."\n\n");
end

local function record_stanza(stanza, session, verb)
	local flattened = tostring(stanza:indent(2, "\t"));
	record(session.scansion_id.." "..verb..":\n\t"..flattened.."\n\n");
end

local function record_stanza_in(stanza, session)
	if stanza.attr.xmlns == nil then
		local copy = st.clone(stanza);
		copy.attr.from = nil;
		record_stanza(copy, session, "sends")
	end
	return stanza;
end

local function record_stanza_out(stanza, session)
	if stanza.attr.xmlns == nil then
		if not (stanza.name == "iq" and stanza:get_child("bind", "urn:ietf:params:xml:ns:xmpp-bind")) then
			local copy = st.clone(stanza);
			if copy.attr.to == session.full_jid then
				copy.attr.to = nil;
			end
			record_stanza(copy, session, "receives");
		end
	end
	return stanza;
end

module:hook("resource-bind", function (event)
	local session = event.session;
	if not users[session.username] then
		users[session.username] = {
			character = table.remove(names, 1) or id.short();
			devices = {};
			n_devices = 0;
		};
	end
	local user = users[session.username];
	local device = user.devices[session.resource];
	if not device then
		user.n_devices = user.n_devices + 1;
		device = devices[user.n_devices] or ("device"..id.short());
		user.devices[session.resource] = device;
	end
	session.scansion_character = user.character;
	session.scansion_device = device;
	session.scansion_id = user.character..(device ~= "" and "'s "..device or device);

	record_object("Client", session.scansion_id, {
		jid = session.full_jid,
		password = "password",
	});

	module:log("info", "Connected: %s", session.scansion_id);
	record_event(session, "connects");

	filters.add_filter(session, "stanzas/in", record_stanza_in);
	filters.add_filter(session, "stanzas/out", record_stanza_out);
end);

module:hook("resource-unbind", function (event)
	local session = event.session;
	if session.scansion_id then
		record_event(session, "disconnects");
	end
end)

record_header("# mod_scansion_record on host '"..module.host.."' recording started "..dt.datetime().."\n\n");

record[[
-----

]]

module:hook_global("server-stopping", function ()
	record("# recording ended on "..dt.datetime().."\n");
	module:log("info", "Scansion recording available in %s", header_file);
end);

prosody.events.add_handler("server-cleanup", function ()
	scan:seek("set", 0);
	for line in scan:lines() do
		head:write(line, "\n");
	end
	scan:close();
	os.remove(record_file);
	head:close()
end);