webrick/server.rb: stop immediately

* lib/webrick/server.rb (WEBrick::GenericServer#start): flush
  shutdown pipe.
* lib/webrick/server.rb (WEBrick::GenericServer#stop): request the
  server to stop immediately by sending data via shutdown pipe.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@51231 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

3 files changed, 34 insertions, 11 deletions

diff --git a/ChangeLog b/ChangeLog
index 303ee39666..97c344155c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+Tue Jul 14 11:20:13 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* lib/webrick/server.rb (WEBrick::GenericServer#start): flush
+	  shutdown pipe.
+
+	* lib/webrick/server.rb (WEBrick::GenericServer#stop): request the
+	  server to stop immediately by sending data via shutdown pipe.
+
 Mon Jul 13 23:58:08 2015  Stefano Tortarolo  <stefano.tortarolo@gmail.com>
 
 	* lib/webrick/httpproxy.rb (WEBrick::HTTPProxyServer#do_CONNECT):
diff --git a/lib/webrick/server.rb b/lib/webrick/server.rb
index 5ada88ac73..1d87cdae70 100644
--- a/lib/webrick/server.rb
+++ b/lib/webrick/server.rb
@@ -172,8 +172,13 @@ module WEBrick
         begin
           while @status == :Running
             begin
-              if svrs = IO.select([shutdown_pipe[0], *@listeners], nil, nil, 2.0)
-                if svrs[0].include? shutdown_pipe[0]
+              sp = shutdown_pipe[0]
+              if svrs = IO.select([sp, *@listeners], nil, nil, 2.0)
+                if svrs[0].include? sp
+                  # swallow shutdown pipe
+                  buf = String.new
+                  nil while String ===
+                            sp.read_nonblock([sp.nread, 8].max, buf, exception: false)
                   break
                 end
                 svrs[0].each{|svr|
@@ -221,6 +226,8 @@ module WEBrick
       if @status == :Running
         @status = :Shutdown
       end
+
+      alarm_shutdown_pipe {|f| f.write_nonblock("\0")}
     end
 
     ##
@@ -230,15 +237,7 @@ module WEBrick
     def shutdown
       stop
 
-      shutdown_pipe = @shutdown_pipe # another thread may modify @shutdown_pipe.
-      if shutdown_pipe
-        if !shutdown_pipe[1].closed?
-          begin
-            shutdown_pipe[1].close
-          rescue IOError # closed by another thread.
-          end
-        end
-      end
+      alarm_shutdown_pipe {|f| f.close}
     end
 
     ##
@@ -343,6 +342,18 @@ module WEBrick
       }
     end
 
+    def alarm_shutdown_pipe
+      _, pipe = @shutdown_pipe # another thread may modify @shutdown_pipe.
+      if pipe
+        if !pipe.closed?
+          begin
+            yield pipe
+          rescue IOError # closed by another thread.
+          end
+        end
+      end
+    end
+
     def cleanup_listener
       @listeners.each{|s|
         if @logger.debug?
diff --git a/test/webrick/test_server.rb b/test/webrick/test_server.rb
index 37b1dd50ca..1a720361cc 100644
--- a/test/webrick/test_server.rb
+++ b/test/webrick/test_server.rb
@@ -137,8 +137,12 @@ class TestWEBrickServer < Test::Unit::TestCase
         flunk "unexpected log: #{msg.inspect}"
       end
     end
+    client_thread = nil
+    wakeup = -> {client_thread.wakeup}
     warn_flunk = WEBrick::Log.new(log, WEBrick::BasicLog::WARN)
     server = WEBrick::HTTPServer.new(
+      :StartCallback => wakeup,
+      :StopCallback => wakeup,
       :BindAddress => '0.0.0.0',
       :Port => 0,
       :Logger => warn_flunk)