rename ExtensionRAIIObject.h -> RAIIObjectsForParser.h


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@91008 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Parse/RAIIObjectsForParser.h b/lib/Parse/RAIIObjectsForParser.h
new file mode 100644
index 0000000..d642da5
--- /dev/null
+++ b/lib/Parse/RAIIObjectsForParser.h
@@ -0,0 +1,41 @@
+//===--- RAIIObjectsForParser.h - RAII helpers for the parser ---*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines and implements the some simple RAII objects that are used
+// by the parser to manage bits in recursion.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_PARSE_RAII_OBJECTS_FOR_PARSER_H
+#define LLVM_CLANG_PARSE_RAII_OBJECTS_FOR_PARSER_H
+
+#include "clang/Parse/ParseDiagnostic.h"
+
+namespace clang {
+
+  /// ExtensionRAIIObject - This saves the state of extension warnings when
+  /// constructed and disables them.  When destructed, it restores them back to
+  /// the way they used to be.  This is used to handle __extension__ in the
+  /// parser.
+  class ExtensionRAIIObject {
+    void operator=(const ExtensionRAIIObject &);     // DO NOT IMPLEMENT
+    ExtensionRAIIObject(const ExtensionRAIIObject&); // DO NOT IMPLEMENT
+    Diagnostic &Diags;
+  public:
+    ExtensionRAIIObject(Diagnostic &diags) : Diags(diags) {
+      Diags.IncrementAllExtensionsSilenced();
+    }
+
+    ~ExtensionRAIIObject() {
+      Diags.DecrementAllExtensionsSilenced();
+    }
+  };
+}
+
+#endif