1 files changed, 183 insertions, 0 deletions
diff --git a/lib/mutex_m.rb b/lib/mutex_m.rb
new file mode 100644
index 0000000000..823888e72f
--- /dev/null
+++ b/lib/mutex_m.rb
@@ -0,0 +1,183 @@
+#
+#   mutex_m.rb - 
+#   	$Release Version: 2.0$
+#   	$Revision: 1.2 $
+#   	$Date: 1997/07/25 02:43:21 $
+#       Original from mutex.rb
+#   	by Keiju ISHITSUKA(SHL Japan Inc.)
+#
+# --
+#   Usage:
+#	require "mutex_m.rb"
+#	obj = Object.new
+#	obj.extend Mutex_m
+#	...
+#	後はMutexと同じ使い方
+#
+
+require "finalize"
+
+module Mutex_m
+  def Mutex_m.extend_object(obj)
+    if Fixnum === obj or TRUE === obj or FALSE === obj or nil == obj
+      raise TypeError, "Mutex_m can't extend to this class(#{obj.type})"
+    else
+      begin
+	eval "class << obj
+		@mu_locked
+	      end"
+	obj.extend(For_primitive_object)
+      rescue TypeError
+	obj.extend(For_general_object)
+      end
+    end
+  end
+  
+  def mu_extended
+    unless (defined? locked? and
+	    defined? lock and
+	    defined? unlock and
+	    defined? try_lock and
+	    defined? synchronize)
+      eval "class << self
+	alias locked mu_locked?
+	alias lock mu_lock
+	alias unlock mu_unlock
+	alias try_lock mu_try_lock
+	alias synchronize mu_synchronize
+      end"
+    end
+  end
+  
+  def mu_synchronize
+    begin
+      mu_lock
+      yield
+    ensure
+      mu_unlock
+    end
+  end
+  
+  module For_general_object
+    include Mutex_m
+    
+    def For_general_object.extend_object(obj)
+      super
+      obj.mu_extended
+    end
+    
+    def mu_extended
+      super
+      @mu_waiting = []
+      @mu_locked = FALSE;
+    end
+
+    def mu_locked?
+      @mu_locked
+    end
+
+    def mu_try_lock
+      result = FALSE
+      Thread.critical = TRUE
+      unless @mu_locked
+	@mu_locked = TRUE
+	result = TRUE
+      end
+      Thread.critical = FALSE
+      result
+    end
+
+    def mu_lock
+      while (Thread.critical = TRUE; @mu_locked)
+	@mu_waiting.push Thread.current
+	Thread.stop
+      end
+      @mu_locked = TRUE
+      Thread.critical = FALSE
+      self
+    end
+
+    def mu_unlock
+      return unless @mu_locked
+      Thread.critical = TRUE
+      wait = @mu_waiting
+      @mu_waiting = []
+      @mu_locked = FALSE
+      Thread.critical = FALSE
+      for w in wait
+	w.run
+      end
+      self
+    end
+
+  end
+
+  module For_primitive_object
+    include Mutex_m
+    Mu_Locked = Hash.new
+    
+    def For_primitive_object.extend_object(obj)
+      super
+      obj.mu_extended
+      Finalizer.add(obj, For_primitive_object, :mu_finalize)
+    end
+    
+    def For_primitive_object.mu_finalize(id)
+      Thread.critical = TRUE
+      if wait = Mu_Locked.delete(id)
+	# wait == [] ときだけ GCされるので, for w in wait は意味なし.
+	Thread.critical = FALSE
+	for w in wait
+	  w.run
+	end
+      else
+	Thread.critical = FALSE
+      end
+      self
+    end
+    
+    def mu_locked?
+      Mu_Locked.key?(self.id)
+    end
+
+    def mu_try_lock
+      Thread.critical = TRUE
+      if Mu_Locked.key?(self.id)
+	ret = FALSE
+      else
+	Mu_Locked[self.id] = []
+	Finalizer.set(self, For_primitive_object, :mu_delete_Locked)
+	ret = TRUE
+      end
+      Thread.critical = FALSE
+      ret
+    end
+
+    def mu_lock
+      while (Thread.critical = TRUE; w = Mu_Locked[self.id])
+	w.push Thread.current
+	Thread.stop
+      end
+      Mu_Locked[self.id] = []
+      Finalizer.add(self, For_primitive_object, :mu_delete_Locked)
+      Thread.critical = FALSE
+      self
+    end
+
+    def mu_unlock
+      Thread.critical = TRUE
+      if wait = Mu_Locked.delete(self.id)
+	Finalizer.delete(self, For_primitive_object, :mu_finalize)
+	Thread.critical = FALSE
+	for w in wait
+	  w.run
+	end
+      else
+	Thread.critical = FALSE
+      end
+      self
+    end
+  end
+end
+
+