Mojo: Split off the C++ parts of mojo/public/c/system macros.h to their own file.

mojo/public/cpp/system/macros.h

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef MOJO_PUBLIC_CPP_SYSTEM_MACROS_H_
+#define MOJO_PUBLIC_CPP_SYSTEM_MACROS_H_
+
+#include "mojo/public/c/system/macros.h"
+
+// Annotate a virtual method indicating it must be overriding a virtual method
+// in the parent class. Use like:
+//   virtual void foo() OVERRIDE;
+#if defined(_MSC_VER) || defined(__clang__)
+#define MOJO_OVERRIDE override
+#else
+#define MOJO_OVERRIDE
+#endif
+
+// A macro to disallow the copy constructor and operator= functions.
+// This should be used in the private: declarations for a class.
+#define MOJO_DISALLOW_COPY_AND_ASSIGN(TypeName) \
+    TypeName(const TypeName&); \
+    void operator=(const TypeName&)
+
+// Used to calculate the number of elements in an array.
+// (See |arraysize()| in Chromium's base/basictypes.h for more details.)
+namespace mojo {
+template <typename T, size_t N>
+char (&ArraySizeHelper(T (&array)[N]))[N];
+#if !defined(_MSC_VER)
+template <typename T, size_t N>
+char (&ArraySizeHelper(const T (&array)[N]))[N];
+#endif
+}  // namespace mojo
+#define MOJO_ARRAYSIZE(array) (sizeof(::mojo::ArraySizeHelper(array)))
+
+// Used to make a type move-only in C++03. See Chromium's base/move.h for more
+// details.
+#define MOJO_MOVE_ONLY_TYPE_FOR_CPP_03(type, rvalue_type) \
+   private: \
+    struct rvalue_type { \
+      explicit rvalue_type(type* object) : object(object) {} \
+      type* object; \
+    }; \
+    type(type&); \
+    void operator=(type&); \
+   public: \
+    operator rvalue_type() { return rvalue_type(this); } \
+    type Pass() { return type(rvalue_type(this)); } \
+    typedef void MoveOnlyTypeForCPP03; \
+   private:
+
+#endif  // MOJO_PUBLIC_CPP_SYSTEM_MACROS_H_