scopedbitmapaccess.hxx

Go to the documentation of this file.

/* -*- 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_VCL_SCOPEDBITMAPACCESS_HXX
#define INCLUDED_VCL_SCOPEDBITMAPACCESS_HXX

#include <sal/types.h>

namespace vcl
{

template < class Access, class Bitmap, Access* (Bitmap::* Acquire)() > class ScopedBitmapAccess
{
public:
    explicit ScopedBitmapAccess( Bitmap& rBitmap ) :
        mpAccess( nullptr ),
        mpBitmap( &rBitmap )
    {
        mpAccess = (mpBitmap->*Acquire)();
    }

    ScopedBitmapAccess( Access* pAccess, Bitmap& rBitmap ) :
        mpAccess( pAccess ),
        mpBitmap( &rBitmap )
    {
    }

    ScopedBitmapAccess( ) :
        mpAccess( nullptr ),
        mpBitmap( nullptr )
    {
    }

    // Move semantics
    ScopedBitmapAccess &operator=(ScopedBitmapAccess&&other)
    {
        mpAccess=other.mpAccess;
        mpBitmap=other.mpBitmap;
        other.mpAccess = nullptr;
        other.mpBitmap = nullptr;
        return *this;
     }

    // Disable copy from lvalue.
    ScopedBitmapAccess(const ScopedBitmapAccess&) = delete;
    ScopedBitmapAccess &operator=(const ScopedBitmapAccess&) = delete;

    ~ScopedBitmapAccess() COVERITY_NOEXCEPT_FALSE
    {
        if (mpAccess)
           mpBitmap->ReleaseAccess( mpAccess );
    }

    void reset()
    {
        if (mpAccess)
        {
           mpBitmap->ReleaseAccess( mpAccess );
           mpAccess = nullptr;
        }
    }

    bool operator!() const { return !mpAccess; }
    explicit operator bool() const
    {
        return mpAccess;
    }

    Access*         get() { return mpAccess; }
    const Access*   get() const { return mpAccess; }

    Access*         operator->() { return mpAccess; }
    const Access*   operator->() const { return mpAccess; }

    Access&         operator*() { return *mpAccess; }
    const Access&   operator*() const { return *mpAccess; }

private:
    Access*     mpAccess;
    Bitmap*     mpBitmap;
};

}

#endif // INCLUDED_VCL_SCOPEDBITMAPACCESS_HXX

/* vim:set shiftwidth=4 softtabstop=4 expandtab: */