From 886d6d168fdc777c4017011e6acaf382aa628456 Mon Sep 17 00:00:00 2001 From: Matthew Wild Date: Sun, 10 Jan 2010 23:49:38 +0000 Subject: mod_posix: Lock pidfile when in use, shut down if we can't write or lock the pidfile --- plugins/mod_posix.lua | 35 +++++++++++++++++++++++------------ 1 file changed, 23 insertions(+), 12 deletions(-) (limited to 'plugins/mod_posix.lua') diff --git a/plugins/mod_posix.lua b/plugins/mod_posix.lua index b75b9610..8b0bd399 100644 --- a/plugins/mod_posix.lua +++ b/plugins/mod_posix.lua @@ -19,6 +19,8 @@ end local logger_set = require "util.logger".setwriter; +local lfs = require "lfs"; + local prosody = _G.prosody; module.host = "*"; -- we're a global module @@ -59,28 +61,37 @@ module:add_event_hook("server-starting", function () 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); + pidfile_handle, err = io.open(pidfile, "a+"); + 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:write(tostring(pposix.getpid())); + pidfile_handle:flush(); + end end end end -- cgit v1.2.3