1 files changed, 33 insertions, 12 deletions

diff --git a/ext/tk/lib/tk/canvas.rb b/ext/tk/lib/tk/canvas.rb
index c30fd79bb9..fceadd5e9c 100644
--- a/ext/tk/lib/tk/canvas.rb
+++ b/ext/tk/lib/tk/canvas.rb
@@ -1,6 +1,5 @@
 #
 #               tk/canvas.rb - Tk canvas classes
-#                       $Date$
 #                       by Yukihiro Matsumoto <matz@caelum.co.jp>
 #
 require 'tk'
@@ -40,7 +39,7 @@ module TkCanvasItemConfig
   private :__item_pathname
 end
 
-class TkCanvas<TkWindow
+class Tk::Canvas<TkWindow
   include TkCanvasItemConfig
   include Tk::Scrollable
 
@@ -186,11 +185,17 @@ class TkCanvas<TkWindow
   end
 
   def delete(*args)
-    if TkcItem::CItemID_TBL[self.path]
+    tbl = nil
+    TkcItem::CItemID_TBL.mutex.synchronize{
+      tbl = TkcItem::CItemID_TBL[self.path]
+    }
+    if tbl
       args.each{|tag|
         find('withtag', tag).each{|item|
           if item.kind_of?(TkcItem)
-            TkcItem::CItemID_TBL[self.path].delete(item.id)
+            TkcItem::CItemID_TBL.mutex.synchronize{
+              tbl.delete(item.id)
+            }
           end
         }
       }
@@ -573,6 +578,10 @@ class TkCanvas<TkWindow
   end
 end
 
+#TkCanvas = Tk::Canvas unless Object.const_defined? :TkCanvas
+Tk.__set_toplevel_aliases__(:Tk, Tk::Canvas, :TkCanvas)
+
+
 class TkcItem<TkObject
   extend Tk
   include TkcTagAccess
@@ -581,9 +590,12 @@ class TkcItem<TkObject
 
   CItemTypeName = nil
   CItemTypeToClass = {}
+
   CItemID_TBL = TkCore::INTERP.create_table
 
-  TkCore::INTERP.init_ip_env{ CItemID_TBL.clear }
+  TkCore::INTERP.init_ip_env{
+    CItemID_TBL.mutex.synchronize{ CItemID_TBL.clear }
+  }
 
   def TkcItem.type2class(type)
     CItemTypeToClass[type]
@@ -591,8 +603,13 @@ class TkcItem<TkObject
 
   def TkcItem.id2obj(canvas, id)
     cpath = canvas.path
-    return id unless CItemID_TBL[cpath]
-    CItemID_TBL[cpath][id]? CItemID_TBL[cpath][id]: id
+    CItemID_TBL.mutex.synchronize{
+      if CItemID_TBL[cpath]
+        CItemID_TBL[cpath][id]? CItemID_TBL[cpath][id]: id
+      else
+        id
+      end
+    }
   end
 
   ########################################
@@ -658,15 +675,17 @@ class TkcItem<TkObject
   ########################################
 
   def initialize(parent, *args)
-    #unless parent.kind_of?(TkCanvas)
-    #  fail ArgumentError, "expect TkCanvas for 1st argument"
+    #unless parent.kind_of?(Tk::Canvas)
+    #  fail ArgumentError, "expect Tk::Canvas for 1st argument"
     #end
     @parent = @c = parent
     @path = parent.path
 
     @id = create_self(*args) # an integer number as 'canvas item id'
-    CItemID_TBL[@path] = {} unless CItemID_TBL[@path]
-    CItemID_TBL[@path][@id] = self
+    CItemID_TBL.mutex.synchronize{
+      CItemID_TBL[@path] = {} unless CItemID_TBL[@path]
+      CItemID_TBL[@path][@id] = self
+    }
   end
   def create_self(*args)
     self.class.create(@c, *args) # return an integer number as 'canvas item id'
@@ -687,7 +706,9 @@ class TkcItem<TkObject
 
   def delete
     @c.delete @id
-    CItemID_TBL[@path].delete(@id) if CItemID_TBL[@path]
+    CItemID_TBL.mutex.synchronize{
+      CItemID_TBL[@path].delete(@id) if CItemID_TBL[@path]
+    }
     self
   end
   alias remove  delete