implement simple VFS to support caching during project parsing

sync up with qt creator - for qmake itself, this is just a minor
refactoring.

Change-Id: I833253f81c3159056fab2ff888f293b36cc2ef56
Reviewed-by: Daniel Teske <daniel.teske@digia.com>
(cherry picked from qtcreator/66802ef8bf7989dc025e34bf91d93576189c483c)
(cherry picked from qtcreator/69542826fa643a0fed2fc9e717f072c2852dc017)
(cherry picked from qtcreator/196424115338fb9a535810704b7d814d318b0462)
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>

1 files changed, 85 insertions, 0 deletions

diff --git a/qmake/library/qmakevfs.h b/qmake/library/qmakevfs.h
new file mode 100644
index 0000000000..13204ece9d
--- /dev/null
+++ b/qmake/library/qmakevfs.h
@@ -0,0 +1,85 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the qmake application of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QMAKEVFS_H
+#define QMAKEVFS_H
+
+#include "qmake_global.h"
+
+# include <qiodevice.h>
+#ifndef PROEVALUATOR_FULL
+# include <qhash.h>
+# include <qstring.h>
+# ifdef PROEVALUATOR_THREAD_SAFE
+#  include <qmutex.h>
+# endif
+#endif
+
+QT_BEGIN_NAMESPACE
+
+class QMAKE_EXPORT QMakeVfs
+{
+public:
+    QMakeVfs();
+
+    bool writeFile(const QString &fn, QIODevice::OpenMode mode, const QString &contents, QString *errStr);
+    bool readFile(const QString &fn, QString *contents, QString *errStr);
+    bool exists(const QString &fn);
+
+#ifndef PROEVALUATOR_FULL
+    void invalidateCache();
+    void invalidateContents();
+#endif
+
+private:
+#ifndef PROEVALUATOR_FULL
+# ifdef PROEVALUATOR_THREAD_SAFE
+    QMutex m_mutex;
+# endif
+    QHash<QString, QString> m_files;
+    QString m_magicMissing;
+    QString m_magicExisting;
+#endif
+};
+
+QT_END_NAMESPACE
+
+#endif // QMAKEVFS_H