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 = "0.3.3";
  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 logger_set = require "util.logger".setwriter;
  21
  22 local lfs = require "lfs";
  23 local stat = lfs.attributes;
  24
  25 local prosody = _G.prosody;
  26
  27 module.host = "*"; -- we're a global module
  28
  29 local umask = module:get_option("umask") or "027";
  30 pposix.umask(umask);
  31
  32 -- Allow switching away from root, some people like strange ports.
  33 module:add_event_hook("server-started", function ()
  34                 local uid = module:get_option("setuid");
  35                 local gid = module:get_option("setgid");
  36                 if gid then
  37                         local success, msg = pposix.setgid(gid);
  38                         if success then
  39                                 module:log("debug", "Changed group to "..gid.." successfully.");
  40                         else
  41                                 module:log("error", "Failed to change group to "..gid..". Error: "..msg);
  42                                 prosody.shutdown("Failed to change group to "..gid);
  43                         end
  44                 end
  45                 if uid then
  46                         local success, msg = pposix.setuid(uid);
  47                         if success then
  48                                 module:log("debug", "Changed user to "..uid.." successfully.");
  49                         else
  50                                 module:log("error", "Failed to change user to "..uid..". Error: "..msg);
  51                                 prosody.shutdown("Failed to change user to "..uid);
  52                         end
  53                 end
  54         end);
  55
  56 -- Don't even think about it!
  57 if not prosody.start_time then -- server-starting
  58         local suid = module:get_option("setuid");
  59         if not suid or suid == 0 or suid == "root" then
  60                 if pposix.getuid() == 0 and not module:get_option("run_as_root") then
  61                         module:log("error", "Danger, Will Robinson! Prosody doesn't need to be run as root, so don't do it!");
  62                         module:log("error", "For more information on running Prosody as root, see http://prosody.im/doc/root");
  63                         prosody.shutdown("Refusing to run as root");
  64                 end
  65         end
  66 end
  67
  68 local pidfile;
  69 local pidfile_handle;
  70
  71 local function remove_pidfile()
  72         if pidfile_handle then
  73                 pidfile_handle:close();
  74                 os.remove(pidfile);
  75                 pidfile, pidfile_handle = nil, nil;
  76         end
  77 end
  78
  79 local function write_pidfile()
  80         if pidfile_handle then
  81                 remove_pidfile();
  82         end
  83         pidfile = module:get_option("pidfile");
  84         if pidfile then
  85                 local err;
  86                 local mode = stat(pidfile) and "r+" or "w+";
  87                 pidfile_handle, err = io.open(pidfile, mode);
  88                 if not pidfile_handle then
  89                         module:log("error", "Couldn't write pidfile at %s; %s", pidfile, err);
  90                         prosody.shutdown("Couldn't write pidfile");
  91                 else
  92                         if not lfs.lock(pidfile_handle, "w") then -- Exclusive lock
  93                                 local other_pid = pidfile_handle:read("*a");
  94                                 module:log("error", "Another Prosody instance seems to be running with PID %s, quitting", other_pid);
  95                                 pidfile_handle = nil;
  96                                 prosody.shutdown("Prosody already running");
  97                         else
  98                                 pidfile_handle:close();
  99                                 pidfile_handle, err = io.open(pidfile, "w+");
 100                                 if not pidfile_handle then
 101                                         module:log("error", "Couldn't write pidfile at %s; %s", pidfile, err);
 102                                         prosody.shutdown("Couldn't write pidfile");
 103                                 else
 104                                         if lfs.lock(pidfile_handle, "w") then
 105                                                 pidfile_handle:write(tostring(pposix.getpid()));
 106                                                 pidfile_handle:flush();
 107                                         end
 108                                 end
 109                         end
 110                 end
 111         end
 112 end
 113
 114 local syslog_opened
 115 function syslog_sink_maker(config)
 116         if not syslog_opened then
 117                 pposix.syslog_open("prosody");
 118                 syslog_opened = true;
 119         end
 120         local syslog, format = pposix.syslog_log, string.format;
 121         return function (name, level, message, ...)
 122                         if ... then
 123                                 syslog(level, format(message, ...));
 124                         else
 125                                 syslog(level, message);
 126                         end
 127                 end;
 128 end
 129 require "core.loggingmanager".register_sink_type("syslog", syslog_sink_maker);
 130
 131 local daemonize = module:get_option("daemonize");
 132 if daemonize == nil then
 133         local no_daemonize = module:get_option("no_daemonize"); --COMPAT w/ 0.5
 134         daemonize = not no_daemonize;
 135         if no_daemonize ~= nil then
 136                 module:log("warn", "The 'no_daemonize' option is now replaced by 'daemonize'");
 137                 module:log("warn", "Update your config from 'no_daemonize = %s' to 'daemonize = %s'", tostring(no_daemonize), tostring(daemonize));
 138         end
 139 end
 140
 141 if daemonize then
 142         local function daemonize_server()
 143                 local ok, ret = pposix.daemonize();
 144                 if not ok then
 145                         module:log("error", "Failed to daemonize: %s", ret);
 146                 elseif ret and ret > 0 then
 147                         os.exit(0);
 148                 else
 149                         module:log("info", "Successfully daemonized to PID %d", pposix.getpid());
 150                         write_pidfile();
 151                 end
 152         end
 153         if not prosody.start_time then -- server-starting
 154                 daemonize_server();
 155         end
 156 else
 157         -- Not going to daemonize, so write the pid of this process
 158         write_pidfile();
 159 end
 160
 161 module:add_event_hook("server-stopped", remove_pidfile);
 162
 163 -- Set signal handlers
 164 if signal.signal then
 165         signal.signal("SIGTERM", function ()
 166                 module:log("warn", "Received SIGTERM");
 167                 prosody.unlock_globals();
 168                 prosody.shutdown("Received SIGTERM");
 169                 prosody.lock_globals();
 170         end);
 171
 172         signal.signal("SIGHUP", function ()
 173                 module:log("info", "Received SIGHUP");
 174                 prosody.reload_config();
 175                 prosody.reopen_logfiles();
 176         end);
 177
 178         signal.signal("SIGINT", function ()
 179                 module:log("info", "Received SIGINT");
 180                 prosody.unlock_globals();
 181                 prosody.shutdown("Received SIGINT");
 182                 prosody.lock_globals();
 183         end);
 184 end