- If a player, including a monitor, stuck at the time of sending

  messages to the wire, which means that the giant lock was locked,
  it might have prevented other players from processing until
  timeout occurred. This issue has been fixed. (Closes #12555)

diff --git a/changelog b/changelog
index 2211823..244cc29 100644 (file)
--- a/changelog
+++ b/changelog
@@ -5,6 +5,10 @@
            record file instead of after the last move, which allows other
            applications watching a game to recognize players in the middle 
            of the game. (Closes #12821)
+         - If a player, including a monitor, stuck at the time of sending
+           messages to the wire, which means that the giant lock was locked,
+           it might have prevented other players from processing until
+           timeout occurred. This issue has been fixed. (Closes #12555)
 
 2008-06-27 Daigo Moriwaki <daigo at debian dot org>
 

diff --git a/shogi_server/player.rb b/shogi_server/player.rb
index c9777e1..b6d5404 100644 (file)
--- a/shogi_server/player.rb
+++ b/shogi_server/player.rb
@@ -110,7 +110,8 @@ class Player < BasicPlayer
     @sente = nil
     @socket_buffer = []
     @main_thread = Thread::current
-    @mutex_write_guard = Mutex.new
+    @write_queue = Queue.new
+    start_write_thread
   end
 
   attr_accessor :socket, :status
@@ -124,7 +125,8 @@ class Player < BasicPlayer
       @game.kill(self)
     end
     finish
-    Thread::kill(@main_thread) if @main_thread
+    Thread::kill(@main_thread)  if @main_thread
+    Thread::kill(@write_thread) if @write_thread
   end
 
   def finish
@@ -133,28 +135,50 @@ class Player < BasicPlayer
       log_message(sprintf("user %s finish", @name))    
       begin
 #        @socket.close if (! @socket.closed?)
+        write_safe(nil)
+        @write_thread.join
       rescue
         log_message(sprintf("user %s finish failed", @name))    
       end
     end
   end
 
-  def write_safe(str)
-    @mutex_write_guard.synchronize do
-      begin
-        if @socket.closed?
-          log_warning("%s's socket has been closed." % [@name])
-          return
-        end
-        if r = select(nil, [@socket], nil, 20)
-          r[1].first.write(str)
-        else
-          log_error("Sending a message to #{@name} timed up.")
+  def start_write_thread
+    @write_thread = Thread.start do
+      Thread.pass
+      while !@socket.closed?
+        str = ""
+        begin
+          begin
+            timeout(5) do
+              str = @write_queue.deq
+            end
+            if str == nil
+              break
+            end
+          rescue TimeoutError
+            next
+          end
+          if r = select(nil, [@socket], nil, 20)
+            r[1].first.write(str)
+          else
+            log_error("Sending a message to #{@name} timed up.")
+          end
+        rescue Exception => ex
+          log_error("Failed to send a message to #{@name}. #{ex.class}: #{ex.message}\t#{ex.backtrace[0]}")
         end
-      rescue Exception => ex
-        log_error("Failed to send a message to #{@name}. #{ex.class}: #{ex.message}\t#{ex.backtrace[0]}")
-      end
-    end
+      end # while loop
+      log_message("terminated %s's write thread" % [@name])
+    end # thread
+  rescue
+
+  end
+
+  #
+  # Note that sending a message is included in the giant lock.
+  #
+  def write_safe(str)
+    @write_queue.enq str
   end
 
   def to_s
@@ -176,6 +200,10 @@ class Player < BasicPlayer
             str = gets_safe(@socket, (@socket_buffer.empty? ? Default_Timeout : 1)) )
       $mutex.lock
       begin
+        if !@write_thread.alive?
+          log_error("%s's write thread is dead. Aborting..." % [@name])
+          return
+        end
         if (@game && @game.turn?(self))
           @socket_buffer << str
           str = @socket_buffer.shift