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 = "0.4.0";
  11
  12 local pposix = assert(require "util.pposix");
  13 if pposix._VERSION ~= want_pposix_version then
  14         module:log("warn", "Unknown version (%s) of binary pposix module, expected %s."
  15                 .. "Perhaps you need to recompile?", tostring(pposix._VERSION), want_pposix_version);
  16 end
  17
  18 local have_signal, signal = pcall(require, "util.signal");
  19 if not have_signal then
  20         module:log("warn", "Couldn't load signal library, won't respond to SIGTERM");
  21 end
  22
  23 local lfs = require "lfs";
  24 local stat = lfs.attributes;
  25
  26 local prosody = _G.prosody;
  27
  28 module:set_global(); -- we're a global module
  29
  30 local umask = module:get_option_string("umask", "027");
  31 pposix.umask(umask);
  32
  33 -- Allow switching away from root, some people like strange ports.
  34 module:hook("server-started", function ()
  35         local uid = module:get_option("setuid");
  36         local gid = module:get_option("setgid");
  37         if gid then
  38                 local success, msg = pposix.setgid(gid);
  39                 if success then
  40                         module:log("debug", "Changed group to %s successfully.", gid);
  41                 else
  42                         module:log("error", "Failed to change group to %s. Error: %s", gid, msg);
  43                         prosody.shutdown("Failed to change group to %s", gid);
  44                 end
  45         end
  46         if uid then
  47                 local success, msg = pposix.setuid(uid);
  48                 if success then
  49                         module:log("debug", "Changed user to %s successfully.", uid);
  50                 else
  51                         module:log("error", "Failed to change user to %s. Error: %s", uid, msg);
  52                         prosody.shutdown("Failed to change user to %s", uid);
  53                 end
  54         end
  55 end);
  56
  57 -- Don't even think about it!
  58 if not prosody.start_time then -- server-starting
  59         local suid = module:get_option("setuid");
  60         if not suid or suid == 0 or suid == "root" then
  61                 if pposix.getuid() == 0 and not module:get_option_boolean("run_as_root") then
  62                         module:log("error", "Danger, Will Robinson! Prosody doesn't need to be run as root, so don't do it!");
  63                         module:log("error", "For more information on running Prosody as root, see https://prosody.im/doc/root");
  64                         prosody.shutdown("Refusing to run as root");
  65                 end
  66         end
  67 end
  68
  69 local pidfile;
  70 local pidfile_handle;
  71
  72 local function remove_pidfile()
  73         if pidfile_handle then
  74                 pidfile_handle:close();
  75                 os.remove(pidfile);
  76                 pidfile, pidfile_handle = nil, nil;
  77         end
  78 end
  79
  80 local function write_pidfile()
  81         if pidfile_handle then
  82                 remove_pidfile();
  83         end
  84         pidfile = module:get_option_path("pidfile", nil, "data");
  85         if pidfile then
  86                 local err;
  87                 local mode = stat(pidfile) and "r+" or "w+";
  88                 pidfile_handle, err = io.open(pidfile, mode);
  89                 if not pidfile_handle then
  90                         module:log("error", "Couldn't write pidfile at %s; %s", pidfile, err);
  91                         prosody.shutdown("Couldn't write pidfile");
  92                 else
  93                         if not lfs.lock(pidfile_handle, "w") then -- Exclusive lock
  94                                 local other_pid = pidfile_handle:read("*a");
  95                                 module:log("error", "Another Prosody instance seems to be running with PID %s, quitting", other_pid);
  96                                 pidfile_handle = nil;
  97                                 prosody.shutdown("Prosody already running");
  98                         else
  99                                 pidfile_handle:close();
 100                                 pidfile_handle, err = io.open(pidfile, "w+");
 101                                 if not pidfile_handle then
 102                                         module:log("error", "Couldn't write pidfile at %s; %s", pidfile, err);
 103                                         prosody.shutdown("Couldn't write pidfile");
 104                                 else
 105                                         if lfs.lock(pidfile_handle, "w") then
 106                                                 pidfile_handle:write(tostring(pposix.getpid()));
 107                                                 pidfile_handle:flush();
 108                                         end
 109                                 end
 110                         end
 111                 end
 112         end
 113 end
 114
 115 local daemonize = module:get_option("daemonize", prosody.installed);
 116
 117 local function remove_log_sinks()
 118         local lm = require "core.loggingmanager";
 119         lm.register_sink_type("console", nil);
 120         lm.register_sink_type("stdout", nil);
 121         lm.reload_logging();
 122 end
 123
 124 if daemonize then
 125         local function daemonize_server()
 126                 module:log("info", "Prosody is about to detach from the console, disabling further console output");
 127                 remove_log_sinks();
 128                 local ok, ret = pposix.daemonize();
 129                 if not ok then
 130                         module:log("error", "Failed to daemonize: %s", ret);
 131                 elseif ret and ret > 0 then
 132                         os.exit(0);
 133                 else
 134                         module:log("info", "Successfully daemonized to PID %d", pposix.getpid());
 135                         write_pidfile();
 136                 end
 137         end
 138         if not prosody.start_time then -- server-starting
 139                 daemonize_server();
 140         end
 141 else
 142         -- Not going to daemonize, so write the pid of this process
 143         write_pidfile();
 144 end
 145
 146 module:hook("server-stopped", remove_pidfile);
 147
 148 -- Set signal handlers
 149 if have_signal then
 150         module:add_timer(0, function ()
 151                 signal.signal("SIGTERM", function ()
 152                         module:log("warn", "Received SIGTERM");
 153                         prosody.unlock_globals();
 154                         prosody.shutdown("Received SIGTERM");
 155                         prosody.lock_globals();
 156                 end);
 157
 158                 signal.signal("SIGHUP", function ()
 159                         module:log("info", "Received SIGHUP");
 160                         prosody.reload_config();
 161                         -- this also reloads logging
 162                 end);
 163
 164                 signal.signal("SIGINT", function ()
 165                         module:log("info", "Received SIGINT");
 166                         prosody.unlock_globals();
 167                         prosody.shutdown("Received SIGINT");
 168                         prosody.lock_globals();
 169                 end);
 170         end);
 171 end