include/comphelper/streamsection.hxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
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   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #ifndef INCLUDED_COMPHELPER_STREAMSECTION_HXX
  21 #define INCLUDED_COMPHELPER_STREAMSECTION_HXX
  22
  23 #include <com/sun/star/io/XMarkableStream.hpp>
  24 #include <com/sun/star/io/XDataInputStream.hpp>
  25 #include <com/sun/star/io/XDataOutputStream.hpp>
  26 #include <comphelper/comphelperdllapi.h>
  27
  28 namespace comphelper
  29 {
  30
  31 /** implements handling for compatibly reading/writing data from/into an input/output stream.
  32     data written in a block secured by this class should be readable by older versions which
  33     use the same mechanism.
  34
  35     @author Frank Schoenheit
  36     @since  00/26/05
  37 */
  38
  39 class COMPHELPER_DLLPUBLIC OStreamSection
  40 {
  41     css::uno::Reference< css::io::XMarkableStream >       m_xMarkStream;
  42     css::uno::Reference< css::io::XDataInputStream >      m_xInStream;
  43     css::uno::Reference< css::io::XDataOutputStream >     m_xOutStream;
  44
  45     sal_Int32   m_nBlockStart;
  46     sal_Int32   m_nBlockLen;
  47
  48 public:
  49     /** starts reading of a "skippable" section of data within the given input stream<BR>
  50         @param      _rxInput    the stream to read from. Must support the
  51                                 com::sun::star::io::XMarkableStream interface
  52     */
  53     OStreamSection(const css::uno::Reference< css::io::XDataInputStream >& _rxInput);
  54
  55     /** starts writing of a "skippable" section of data into the given output stream
  56         @param      _rxOutput           the stream the stream to write to. Must support the
  57                                         com::sun::star::io::XMarkableStream interface
  58         @param      _nPresumedLength    estimation for the length of the upcoming section. If greater 0, this
  59                                         value will be written as section length and corrected (in the dtor) only if
  60                                         needed. If you know how much bytes you are about to write, you may
  61                                         want to use this param, saving some stream operations this way.
  62     */
  63     OStreamSection(const css::uno::Reference< css::io::XDataOutputStream >& _rxOutput, sal_Int32 _nPresumedLength = 0);
  64
  65     /** dtor. <BR>If constructed for writing, the section "opened" by this object will be "closed".<BR>
  66         If constructed for reading, any remaining bytes 'til the end of the section will be skipped.
  67     */
  68     ~OStreamSection();
  69 };
  70
  71 }   // namespace comphelper
  72
  73 #endif // INCLUDED_COMPHELPER_STREAMSECTION_HXX
  74
  75 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */