plugins/mod_posix.lua

   1 -- Prosody IM
   2 -- Copyright (C) 2008-2010 Matthew Wild
   3 -- Copyright (C) 2008-2010 Waqas Hussain
   4 --
   5 -- This project is MIT/X11 licensed. Please see the
   6 -- COPYING file in the source package for more information.
   7 --
   8
   9
  10 local want_pposix_version = "0.3.5";
  11
  12 local pposix = assert(require "util.pposix");
  13 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
  14
  15 local signal = select(2, pcall(require, "util.signal"));
  16 if type(signal) == "string" then
  17         module:log("warn", "Couldn't load signal library, won't respond to SIGTERM");
  18 end
  19
  20 local lfs = require "lfs";
  21 local stat = lfs.attributes;
  22
  23 local prosody = _G.prosody;
  24
  25 module:set_global(); -- we're a global module
  26
  27 local umask = module:get_option("umask") or "027";
  28 pposix.umask(umask);
  29
  30 -- Allow switching away from root, some people like strange ports.
  31 module:hook("server-started", function ()
  32                 local uid = module:get_option("setuid");
  33                 local gid = module:get_option("setgid");
  34                 if gid then
  35                         local success, msg = pposix.setgid(gid);
  36                         if success then
  37                                 module:log("debug", "Changed group to %s successfully.", gid);
  38                         else
  39                                 module:log("error", "Failed to change group to %s. Error: %s", gid, msg);
  40                                 prosody.shutdown("Failed to change group to %s", gid);
  41                         end
  42                 end
  43                 if uid then
  44                         local success, msg = pposix.setuid(uid);
  45                         if success then
  46                                 module:log("debug", "Changed user to %s successfully.", uid);
  47                         else
  48                                 module:log("error", "Failed to change user to %s. Error: %s", uid, msg);
  49                                 prosody.shutdown("Failed to change user to %s", uid);
  50                         end
  51                 end
  52         end);
  53
  54 -- Don't even think about it!
  55 if not prosody.start_time then -- server-starting
  56         local suid = module:get_option("setuid");
  57         if not suid or suid == 0 or suid == "root" then
  58                 if pposix.getuid() == 0 and not module:get_option("run_as_root") then
  59                         module:log("error", "Danger, Will Robinson! Prosody doesn't need to be run as root, so don't do it!");
  60                         module:log("error", "For more information on running Prosody as root, see http://prosody.im/doc/root");
  61                         prosody.shutdown("Refusing to run as root");
  62                 end
  63         end
  64 end
  65
  66 local pidfile;
  67 local pidfile_handle;
  68
  69 local function remove_pidfile()
  70         if pidfile_handle then
  71                 pidfile_handle:close();
  72                 os.remove(pidfile);
  73                 pidfile, pidfile_handle = nil, nil;
  74         end
  75 end
  76
  77 local function write_pidfile()
  78         if pidfile_handle then
  79                 remove_pidfile();
  80         end
  81         pidfile = module:get_option("pidfile");
  82         if pidfile then
  83                 local err;
  84                 local mode = stat(pidfile) and "r+" or "w+";
  85                 pidfile_handle, err = io.open(pidfile, mode);
  86                 if not pidfile_handle then
  87                         module:log("error", "Couldn't write pidfile at %s; %s", pidfile, err);
  88                         prosody.shutdown("Couldn't write pidfile");
  89                 else
  90                         if not lfs.lock(pidfile_handle, "w") then -- Exclusive lock
  91                                 local other_pid = pidfile_handle:read("*a");
  92                                 module:log("error", "Another Prosody instance seems to be running with PID %s, quitting", other_pid);
  93                                 pidfile_handle = nil;
  94                                 prosody.shutdown("Prosody already running");
  95                         else
  96                                 pidfile_handle:close();
  97                                 pidfile_handle, err = io.open(pidfile, "w+");
  98                                 if not pidfile_handle then
  99                                         module:log("error", "Couldn't write pidfile at %s; %s", pidfile, err);
 100                                         prosody.shutdown("Couldn't write pidfile");
 101                                 else
 102                                         if lfs.lock(pidfile_handle, "w") then
 103                                                 pidfile_handle:write(tostring(pposix.getpid()));
 104                                                 pidfile_handle:flush();
 105                                         end
 106                                 end
 107                         end
 108                 end
 109         end
 110 end
 111
 112 local syslog_opened;
 113 function syslog_sink_maker(config)
 114         if not syslog_opened then
 115                 pposix.syslog_open("prosody", module:get_option_string("syslog_facility"));
 116                 syslog_opened = true;
 117         end
 118         local syslog, format = pposix.syslog_log, string.format;
 119         return function (name, level, message, ...)
 120                 if ... then
 121                         syslog(level, format(message, ...));
 122                 else
 123                         syslog(level, message);
 124                 end
 125         end;
 126 end
 127 require "core.loggingmanager".register_sink_type("syslog", syslog_sink_maker);
 128
 129 local daemonize = module:get_option("daemonize");
 130 if daemonize == nil then
 131         local no_daemonize = module:get_option("no_daemonize"); --COMPAT w/ 0.5
 132         daemonize = not no_daemonize;
 133         if no_daemonize ~= nil then
 134                 module:log("warn", "The 'no_daemonize' option is now replaced by 'daemonize'");
 135                 module:log("warn", "Update your config from 'no_daemonize = %s' to 'daemonize = %s'", tostring(no_daemonize), tostring(daemonize));
 136         end
 137 end
 138
 139 local function remove_log_sinks()
 140         local lm = require "core.loggingmanager";
 141         lm.register_sink_type("console", nil);
 142         lm.register_sink_type("stdout", nil);
 143         lm.reload_logging();
 144 end
 145
 146 if daemonize then
 147         local function daemonize_server()
 148                 module:log("info", "Prosody is about to detach from the console, disabling further console output");
 149                 remove_log_sinks();
 150                 local ok, ret = pposix.daemonize();
 151                 if not ok then
 152                         module:log("error", "Failed to daemonize: %s", ret);
 153                 elseif ret and ret > 0 then
 154                         os.exit(0);
 155                 else
 156                         module:log("info", "Successfully daemonized to PID %d", pposix.getpid());
 157                         write_pidfile();
 158                 end
 159         end
 160         if not prosody.start_time then -- server-starting
 161                 daemonize_server();
 162         end
 163 else
 164         -- Not going to daemonize, so write the pid of this process
 165         write_pidfile();
 166 end
 167
 168 module:hook("server-stopped", remove_pidfile);
 169
 170 -- Set signal handlers
 171 if signal.signal then
 172         signal.signal("SIGTERM", function ()
 173                 module:log("warn", "Received SIGTERM");
 174                 prosody.unlock_globals();
 175                 prosody.shutdown("Received SIGTERM");
 176                 prosody.lock_globals();
 177         end);
 178
 179         signal.signal("SIGHUP", function ()
 180                 module:log("info", "Received SIGHUP");
 181                 prosody.reload_config();
 182                 prosody.reopen_logfiles();
 183         end);
 184
 185         signal.signal("SIGINT", function ()
 186                 module:log("info", "Received SIGINT");
 187                 prosody.unlock_globals();
 188                 prosody.shutdown("Received SIGINT");
 189                 prosody.lock_globals();
 190         end);
 191 end