plugins/mod_posix.lua

-- 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 = "0.3.5";

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", tostring(pposix._VERSION), want_pposix_version); end

local signal = select(2, pcall(require, "util.signal"));

if type(signal) == "string" 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.host = "*"; -- we're a global module

local umask = module:get_option("umask") or "027";

pposix.umask(umask);

-- Allow switching away from root, some people like strange ports.

module:hook("server-started", function ()

		local uid = module:get_option("setuid");

		local gid = module:get_option("setgid");

		if gid then

			local success, msg = pposix.setgid(gid);

			if success then

				module:log("debug", "Changed group to "..gid.." successfully.");

			else

				module:log("error", "Failed to change group to "..gid..". Error: "..msg);

				prosody.shutdown("Failed to change group to "..gid);

			end

		end

		if uid then

			local success, msg = pposix.setuid(uid);

			if success then

				module:log("debug", "Changed user to "..uid.." successfully.");

			else

				module:log("error", "Failed to change user to "..uid..". Error: "..msg);

				prosody.shutdown("Failed to change user to "..uid);

			end

		end

	end);

-- Don't even think about it!

if not prosody.start_time then -- server-starting

	local suid = module:get_option("setuid");

	if not suid or suid == 0 or suid == "root" then

		if pposix.getuid() == 0 and not module:get_option("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 http://prosody.im/doc/root");

			prosody.shutdown("Refusing to run as root");

		end

	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("pidfile");

	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");

		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");

			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");

				else

					if lfs.lock(pidfile_handle, "w") then

						pidfile_handle:write(tostring(pposix.getpid()));

						pidfile_handle:flush();

					end

				end

			end

		end

	end

end

local syslog_opened;

function syslog_sink_maker(config)

	if not syslog_opened then

		pposix.syslog_open("prosody");

		syslog_opened = true;

	end

	local syslog, format = pposix.syslog_log, string.format;

	return function (name, level, message, ...)

		if ... then

			syslog(level, format(message, ...));

		else

			syslog(level, message);

		end

	end;

end

require "core.loggingmanager".register_sink_type("syslog", syslog_sink_maker);

local daemonize = module:get_option("daemonize");

if daemonize == nil then

	local no_daemonize = module:get_option("no_daemonize"); --COMPAT w/ 0.5

	daemonize = not no_daemonize;

	if no_daemonize ~= nil then

		module:log("warn", "The 'no_daemonize' option is now replaced by 'daemonize'");

		module:log("warn", "Update your config from 'no_daemonize = %s' to 'daemonize = %s'", tostring(no_daemonize), tostring(daemonize));

	end

end

if daemonize then

	local function daemonize_server()

		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

	if not prosody.start_time then -- server-starting

		daemonize_server();

	end

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 signal.signal then

	signal.signal("SIGTERM", function ()

		module:log("warn", "Received SIGTERM");

		prosody.unlock_globals();

		prosody.shutdown("Received SIGTERM");

		prosody.lock_globals();

	end);

	signal.signal("SIGHUP", function ()

		module:log("info", "Received SIGHUP");

		prosody.reload_config();

		prosody.reopen_logfiles();

	end);

	signal.signal("SIGINT", function ()

		module:log("info", "Received SIGINT");

		prosody.unlock_globals();

		prosody.shutdown("Received SIGINT");

		prosody.lock_globals();

	end);

end