Monster whitespace commit (beware the whitespace monster).

[prosody.git] / plugins / mod_posix.lua

diff --git a/plugins/mod_posix.lua b/plugins/mod_posix.lua
index 8c2c7d7dd5ad44bfe29f6a2564271409584659c5..e86b785450f77152b9ac21959444aef78dbc4104 100644 (file)
--- a/plugins/mod_posix.lua
+++ b/plugins/mod_posix.lua
@@ -1,13 +1,13 @@
 -- Prosody IM
--- Copyright (C) 2008-2009 Matthew Wild
--- Copyright (C) 2008-2009 Waqas Hussain
+-- 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 = "0.3.2";
+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
@@ -19,6 +19,9 @@ end
 
 local logger_set = require "util.logger".setwriter;
 
+local lfs = require "lfs";
+local stat = lfs.attributes;
+
 local prosody = _G.prosody;
 
 module.host = "*"; -- we're a global module
@@ -27,7 +30,7 @@ local umask = module:get_option("umask") or "027";
 pposix.umask(umask);
 
 -- Allow switching away from root, some people like strange ports.
-module:add_event_hook("server-started", function ()
+module:hook("server-started", function ()
                local uid = module:get_option("setuid");
                local gid = module:get_option("setgid");
                if gid then
@@ -51,44 +54,64 @@ module:add_event_hook("server-started", function ()
        end);
 
 -- Don't even think about it!
-module:add_event_hook("server-starting", function ()
-               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
+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
+end
 
-local pidfile_written;
+local pidfile;
+local pidfile_handle;
 
 local function remove_pidfile()
-       if pidfile_written then
-               os.remove(pidfile_written);
-               pidfile_written = nil;
+       if pidfile_handle then
+               pidfile_handle:close();
+               os.remove(pidfile);
+               pidfile, pidfile_handle = nil, nil;
        end
 end
 
 local function write_pidfile()
-       if pidfile_written then
+       if pidfile_handle then
                remove_pidfile();
        end
-       local pidfile = module:get_option("pidfile");
+       pidfile = module:get_option("pidfile");
        if pidfile then
-               local pf, err = io.open(pidfile, "w+");
-               if not pf then
-                       module:log("error", "Couldn't write pidfile; %s", err);
+               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
-                       pf:write(tostring(pposix.getpid()));
-                       pf:close();
-                       pidfile_written = pidfile;
+                       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 
+local syslog_opened;
 function syslog_sink_maker(config)
        if not syslog_opened then
                pposix.syslog_open("prosody");
@@ -96,12 +119,12 @@ function syslog_sink_maker(config)
        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;
+               if ... then
+                       syslog(level, format(message, ...));
+               else
+                       syslog(level, message);
+               end
+       end;
 end
 require "core.loggingmanager".register_sink_type("syslog", syslog_sink_maker);
 
@@ -127,13 +150,15 @@ if daemonize then
                        write_pidfile();
                end
        end
-       module:add_event_hook("server-starting", daemonize_server);
+       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:add_event_hook("server-stopped", remove_pidfile);
+module:hook("server-stopped", remove_pidfile);
 
 -- Set signal handlers
 if signal.signal then