Adds a modified copy of talk/base to webrtc/base. It is the first step in migrating talk/base to webrtc/base.

BUG=N/A
R=andrew@webrtc.org, wu@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/12199004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@6107 4adac7df-926f-26a2-2b94-8c16560cd09d

webrtc/base/constructormagic.h

@@ -0,0 +1,41 @@
+/*
+ *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef WEBRTC_BASE_CONSTRUCTORMAGIC_H_
+#define WEBRTC_BASE_CONSTRUCTORMAGIC_H_
+
+#define DISALLOW_ASSIGN(TypeName) \
+  void operator=(const TypeName&)
+
+// A macro to disallow the evil copy constructor and operator= functions
+// This should be used in the private: declarations for a class.
+// Undefine this, just in case. Some third-party includes have their own
+// version.
+#undef DISALLOW_COPY_AND_ASSIGN
+#define DISALLOW_COPY_AND_ASSIGN(TypeName)    \
+  TypeName(const TypeName&);                    \
+  DISALLOW_ASSIGN(TypeName)
+
+// Alternative, less-accurate legacy name.
+#define DISALLOW_EVIL_CONSTRUCTORS(TypeName) \
+  DISALLOW_COPY_AND_ASSIGN(TypeName)
+
+// A macro to disallow all the implicit constructors, namely the
+// default constructor, copy constructor and operator= functions.
+//
+// This should be used in the private: declarations for a class
+// that wants to prevent anyone from instantiating it. This is
+// especially useful for classes containing only static methods.
+#define DISALLOW_IMPLICIT_CONSTRUCTORS(TypeName) \
+  TypeName();                                    \
+  DISALLOW_EVIL_CONSTRUCTORS(TypeName)
+
+
+#endif  // WEBRTC_BASE_CONSTRUCTORMAGIC_H_