* Merge YARV

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@11439 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

lib/weakref.rb

@@ -1,13 +1,6 @@
-require "delegate"
-
-# WeakRef is a class to represent a reference to an object that is not seen by
-# the tracing phase of the garbage collector.  This allows the referenced
-# object to be garbage collected as if nothing is referring to it. Because
-# WeakRef delegates method calls to the referenced object, it may be used in
-# place of that object, i.e. it is of the same duck type.
+# Weak Reference class that does not bother GCing.
 #
 # Usage:
-#
 #   foo = Object.new
 #   foo = Object.new
 #   p foo.to_s			# original's class
@@ -15,18 +8,21 @@ require "delegate"
 #   p foo.to_s			# should be same class
 #   ObjectSpace.garbage_collect
 #   p foo.to_s			# should raise exception (recycled)
-class WeakRef<Delegator
 
-  # RefError is raised if an object cannot be referenced by a WeakRef.
-  class RefError<StandardError
+require "delegate"
+require 'thread'
+
+class WeakRef < Delegator
+
+  class RefError < StandardError
   end
 
   @@id_map =  {}                # obj -> [ref,...]
   @@id_rev_map =  {}            # ref -> obj
+  @@mutex = Mutex.new
   @@final = lambda {|id|
-    __old_status = Thread.critical
-    Thread.critical = true
-    begin
+    printf "final: %p\n", id
+    @@mutex.synchronize {
       rids = @@id_map[id]
       if rids
 	for rid in rids
@@ -40,20 +36,22 @@ class WeakRef<Delegator
 	@@id_map[rid].delete(id)
 	@@id_map.delete(rid) if @@id_map[rid].empty?
       end
-    ensure
-      Thread.critical = __old_status
-    end
+    }
   }
 
-  # Create a new WeakRef from +orig+.
   def initialize(orig)
-    __setobj__(orig)
+    @__id = orig.object_id
+    printf "orig: %p\n", @__id
+    ObjectSpace.define_finalizer orig, @@final
+    ObjectSpace.define_finalizer self, @@final
+    @@mutex.synchronize {
+      @@id_map[@__id] = [] unless @@id_map[@__id]
+    }
+    @@id_map[@__id].push self.object_id
+    @@id_rev_map[self.object_id] = @__id
     super
   end
 
-  # Return the object this WeakRef references. Raises RefError if the object
-  # has been garbage collected.  The object returned is the object to which
-  # method calls are delegated (see Delegator).
   def __getobj__
     unless @@id_rev_map[self.object_id] == @__id
       Kernel::raise RefError, "Illegal Reference - probably recycled", Kernel::caller(2)
@@ -64,24 +62,9 @@ class WeakRef<Delegator
       Kernel::raise RefError, "Illegal Reference - probably recycled", Kernel::caller(2)
     end
   end
-
   def __setobj__(obj)
-    @__id = obj.object_id
-    ObjectSpace.define_finalizer obj, @@final
-    ObjectSpace.define_finalizer self, @@final
-    __old_status = Thread.critical
-    begin
-      Thread.critical = true
-      @@id_map[@__id] = [] unless @@id_map[@__id]
-    ensure
-      Thread.critical = __old_status
-    end
-    @@id_map[@__id].push self.object_id
-    @@id_rev_map[self.object_id] = @__id
   end
 
-  # Returns true if the referenced object still exists, and false if it has
-  # been garbage collected.
   def weakref_alive?
     @@id_rev_map[self.object_id] == @__id
   end