From 71b4507755f2bd279adb14e6cdc90e1380efa247 Mon Sep 17 00:00:00 2001 From: Eric Wong Date: Tue, 30 Aug 2011 16:18:21 -0700 Subject: avoid potential Logger deadlock in SIGQUIT and SIGUSR1 If any combination of SIGQUIT and SIGUSR1 are sent to a Rainbows! worker in a /very/ short period of time, the Mutex used by the default Logger implementation may deadlock since Mutex synchronization is not reentrant-safe. Users of alternative logger implementations (or monkey-patched ones) are possibly not affected. Users of the logger_mp_safe.rb monkey-patch distributed[1] with unicorn are not affected. [1] http://unicorn.bogomips.org/examples/logger_mp_safe.rb --- lib/rainbows/base.rb | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'lib/rainbows') diff --git a/lib/rainbows/base.rb b/lib/rainbows/base.rb index d1c5c08..54f1d2d 100644 --- a/lib/rainbows/base.rb +++ b/lib/rainbows/base.rb @@ -18,8 +18,11 @@ module Rainbows::Base # we're don't use the self-pipe mechanism in the Rainbows! worker # since we don't defer reopening logs Rainbows::HttpServer::SELF_PIPE.each { |x| x.close }.clear - trap(:USR1) { reopen_worker_logs(worker.nr) } - trap(:QUIT) { Rainbows.quit! } + + # spawn Threads since Logger takes a mutex by default and + # we can't safely lock a mutex in a signal handler + trap(:USR1) { Thread.new { reopen_worker_logs(worker.nr) } } + trap(:QUIT) { Thread.new { Rainbows.quit! } } [:TERM, :INT].each { |sig| trap(sig) { exit!(0) } } # instant shutdown Rainbows::ProcessClient.const_set(:APP, Rainbows.server.app) logger.info "Rainbows! #@use worker_connections=#@worker_connections" -- cgit v1.2.3-24-ge0c7