File

plugins/mod_posix.lua @ 12446:e54b8a5e35ad 0.12

util.random: Test whether util.crand works before using it (fix #1734) util.crand can be configured at compile time to use the Linux getrandom() system call, available from Linux 3.17, but it is still possible to load it with an older kernel lacking that system call, where attempting to use it throws an ENOSYS error. By testing for this on load we can fall back to /dev/urandom in this case.
author Kim Alvefur <zash@zash.se>
date Sat, 02 Apr 2022 16:33:27 +0200
parent 12297:249eb306f668
child 12977:74b9e05af71e
line wrap: on
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-- 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 want_pposix_version = "0.4.0";

local pposix = assert(require "util.pposix");
if pposix._VERSION ~= want_pposix_version then
	module:log("warn", "Unknown version (%s) of binary pposix module, expected %s."
		.. "Perhaps you need to recompile?", tostring(pposix._VERSION), want_pposix_version);
end

local have_signal, signal = pcall(require, "util.signal");
if not have_signal then
	module:log("warn", "Couldn't load signal library, won't respond to SIGTERM");
end

local lfs = require "lfs";
local stat = lfs.attributes;

local prosody = _G.prosody;

module:set_global(); -- we're a global module

local umask = module:get_option_string("umask", "027");
pposix.umask(umask);

-- Don't even think about it!
if not prosody.start_time then -- server-starting
	if pposix.getuid() == 0 and not module:get_option_boolean("run_as_root") then
		module:log("error", "Danger, Will Robinson! Prosody doesn't need to be run as root, so don't do it!");
		module:log("error", "For more information on running Prosody as root, see https://prosody.im/doc/root");
		prosody.shutdown("Refusing to run as root", 1);
	end
end

local pidfile;
local pidfile_handle;

local function remove_pidfile()
	if pidfile_handle then
		pidfile_handle:close();
		os.remove(pidfile);
		pidfile, pidfile_handle = nil, nil;
	end
end

local function write_pidfile()
	if pidfile_handle then
		remove_pidfile();
	end
	pidfile = module:get_option_path("pidfile", nil, "data");
	if pidfile then
		local err;
		local mode = stat(pidfile) and "r+" or "w+";
		pidfile_handle, err = io.open(pidfile, mode);
		if not pidfile_handle then
			module:log("error", "Couldn't write pidfile at %s; %s", pidfile, err);
			prosody.shutdown("Couldn't write pidfile", 1);
		else
			if not lfs.lock(pidfile_handle, "w") then -- Exclusive lock
				local other_pid = pidfile_handle:read("*a");
				module:log("error", "Another Prosody instance seems to be running with PID %s, quitting", other_pid);
				pidfile_handle = nil;
				prosody.shutdown("Prosody already running", 1);
			else
				pidfile_handle:close();
				pidfile_handle, err = io.open(pidfile, "w+");
				if not pidfile_handle then
					module:log("error", "Couldn't write pidfile at %s; %s", pidfile, err);
					prosody.shutdown("Couldn't write pidfile", 1);
				else
					if lfs.lock(pidfile_handle, "w") then
						pidfile_handle:write(tostring(pposix.getpid()));
						pidfile_handle:flush();
					end
				end
			end
		end
	end
end

local daemonize = prosody.opts.daemonize;

if daemonize == nil then
	-- Fall back to config file if not specified on command-line
	daemonize = module:get_option_boolean("daemonize", nil);
	if daemonize ~= nil then
		module:log("warn", "The 'daemonize' option has been deprecated, specify -D or -F on the command line instead.");
		-- TODO: Write some docs and include a link in the warning.
	end
end

local function remove_log_sinks()
	local lm = require "core.loggingmanager";
	lm.register_sink_type("console", nil);
	lm.register_sink_type("stdout", nil);
	lm.reload_logging();
end

if daemonize then
	local function daemonize_server()
		module:log("info", "Prosody is about to detach from the console, disabling further console output");
		remove_log_sinks();
		local ok, ret = pposix.daemonize();
		if not ok then
			module:log("error", "Failed to daemonize: %s", ret);
		elseif ret and ret > 0 then
			os.exit(0);
		else
			module:log("info", "Successfully daemonized to PID %d", pposix.getpid());
			write_pidfile();
		end
	end
	module:hook("server-started", daemonize_server)
else
	-- Not going to daemonize, so write the pid of this process
	write_pidfile();
end

module:hook("server-stopped", remove_pidfile);

-- Set signal handlers
if have_signal then
	module:add_timer(0, function ()
		signal.signal("SIGTERM", function ()
			module:log("warn", "Received SIGTERM");
			prosody.main_thread:run(function ()
				prosody.unlock_globals();
				prosody.shutdown("Received SIGTERM");
				prosody.lock_globals();
			end);
		end);

		signal.signal("SIGHUP", function ()
			module:log("info", "Received SIGHUP");
			prosody.main_thread:run(function ()
				prosody.reload_config();
			end);
			-- this also reloads logging
		end);

		signal.signal("SIGINT", function ()
			module:log("info", "Received SIGINT");
			prosody.main_thread:run(function ()
				prosody.unlock_globals();
				prosody.shutdown("Received SIGINT");
				prosody.lock_globals();
			end);
		end);

		signal.signal("SIGUSR1", function ()
			module:log("info", "Received SIGUSR1");
			module:fire_event("signal/SIGUSR1");
		end);

		signal.signal("SIGUSR2", function ()
			module:log("info", "Received SIGUSR2");
			module:fire_event("signal/SIGUSR2");
		end);
	end);
end

-- For other modules to reference
features = {
	signal_events = true;
};