1 files changed, 84 insertions, 0 deletions
diff --git a/include/comphelper/flagguard.hxx b/include/comphelper/flagguard.hxx
new file mode 100644
index 0000000000..72fa43aa90
--- /dev/null
+++ b/include/comphelper/flagguard.hxx
@@ -0,0 +1,84 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#ifndef INCLUDED_COMPHELPER_FLAGGUARD_HXX
+#define INCLUDED_COMPHELPER_FLAGGUARD_HXX
+
+#include <comphelper/scopeguard.hxx>
+#include <utility>
+
+namespace comphelper
+{
+
+    //= ValueRestorationGuard
+
+    // note: can't store the originalValue in a ValueRestorationGuard member,
+    // because it will be used from base class dtor
+    template <typename T> struct ValueRestorationGuard_Impl
+    {
+        T& rVal;
+        T const originalValue;
+        ValueRestorationGuard_Impl(T& i_valRef)
+            : rVal(i_valRef), originalValue(i_valRef) {}
+        void operator()()
+        {
+            rVal = originalValue;
+        }
+    };
+
+    template <typename T>
+    class ValueRestorationGuard : public ScopeGuard<ValueRestorationGuard_Impl<T>>
+    {
+    public:
+        ValueRestorationGuard(T& i_valRef)
+            : ScopeGuard<ValueRestorationGuard_Impl<T>>(ValueRestorationGuard_Impl(i_valRef))
+        {}
+
+        template <typename T1>
+        ValueRestorationGuard(T& i_valRef, T1&& i_temporaryValue)
+            : ScopeGuard<ValueRestorationGuard_Impl<T>>(ValueRestorationGuard_Impl(i_valRef))
+        {
+            i_valRef = std::forward<T1>(i_temporaryValue);
+        }
+    };
+
+    typedef ValueRestorationGuard<bool> FlagRestorationGuard;
+
+    //= FlagGuard
+
+    // Guarantees that the flag is true within the scope of the guard, and is set to false after
+    // its destruction, regardless of initial flag value
+    class FlagGuard : public FlagRestorationGuard
+    {
+    public:
+        // Set flag to false before passing its reference to base class ctor, so that it would be
+        // reset back to false in base class dtor
+        explicit FlagGuard(bool& i_flagRef)
+            : FlagRestorationGuard((i_flagRef = false), true)
+        {
+        }
+    };
+
+
+} // namespace comphelper
+
+
+#endif // INCLUDED_COMPHELPER_FLAGGUARD_HXX
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */