Fix marking files modified externally as modified

It replaces 59c90e00c1e8b18d120f5b5c15b331b1ee427ace
and d0c537ca759aa7facfdd0efedac5f5385d16ddb9

Task-number: QTCREATORBUG-17048
Change-Id: Ief4b1b72f2e5e7b1711be05d4ea8c03bbbf48fdf
Reviewed-by: Tobias Hunger <tobias.hunger@qt.io>

1 files changed, 53 insertions, 0 deletions

diff --git a/src/libs/utils/guard.h b/src/libs/utils/guard.h
new file mode 100644
index 0000000000..41bfd82288
--- /dev/null
+++ b/src/libs/utils/guard.h
@@ -0,0 +1,53 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt Creator.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+****************************************************************************/
+
+#pragma once
+
+#include "utils_global.h"
+
+namespace Utils {
+
+class QTCREATOR_UTILS_EXPORT Guard
+{
+public:
+    Guard();
+    ~Guard();
+    bool isLocked() const;
+private:
+    int m_lockCount = 0;
+    friend class GuardLocker;
+};
+
+class QTCREATOR_UTILS_EXPORT GuardLocker
+{
+public:
+    GuardLocker(Guard &guard);
+    ~GuardLocker();
+
+private:
+    Guard &m_guard;
+};
+
+} // namespace Utils