include/comphelper/seqstream.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.
   4  *
   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 #ifndef INCLUDED_COMPHELPER_SEQSTREAM_HXX
  20 #define INCLUDED_COMPHELPER_SEQSTREAM_HXX
  21
  22 #include <com/sun/star/uno/Sequence.hxx>
  23 #include <com/sun/star/io/XInputStream.hpp>
  24 #include <com/sun/star/io/XOutputStream.hpp>
  25 #include <com/sun/star/io/XSeekable.hpp>
  26 #include <osl/mutex.hxx>
  27 #include <cppuhelper/implbase.hxx>
  28 #include <comphelper/comphelperdllapi.h>
  29
  30 namespace comphelper
  31 {
  32
  33
  34 // SequenceInputStream
  35 // stream for reading data from a sequence of bytes
  36
  37
  38 class COMPHELPER_DLLPUBLIC SequenceInputStream
  39 : public ::cppu::WeakImplHelper< css::io::XInputStream, css::io::XSeekable >
  40 {
  41     ::osl::Mutex    m_aMutex;
  42     css::uno::Sequence<sal_Int8> const m_aData;
  43     sal_Int32       m_nPos;
  44
  45 public:
  46     SequenceInputStream(css::uno::Sequence<sal_Int8> const & rData);
  47
  48 // css::io::XInputStream
  49     virtual sal_Int32 SAL_CALL readBytes( css::uno::Sequence<sal_Int8>& aData, sal_Int32 nBytesToRead ) override;
  50
  51     virtual sal_Int32 SAL_CALL readSomeBytes( css::uno::Sequence<sal_Int8>& aData, sal_Int32 nMaxBytesToRead ) override;
  52
  53     virtual void SAL_CALL skipBytes( sal_Int32 nBytesToSkip ) override;
  54
  55     virtual sal_Int32 SAL_CALL available(  ) override;
  56
  57     virtual void SAL_CALL closeInput(  ) override;
  58
  59     virtual void SAL_CALL seek( sal_Int64 location ) override;
  60     virtual sal_Int64 SAL_CALL getPosition(  ) override;
  61     virtual sal_Int64 SAL_CALL getLength(  ) override;
  62
  63 private:
  64     inline sal_Int32 avail();
  65 };
  66
  67 // don't export to avoid duplicate WeakImplHelper definitions with MSVC
  68 class SAL_DLLPUBLIC_TEMPLATE OSequenceOutputStream_Base
  69     : public ::cppu::WeakImplHelper< css::io::XOutputStream >
  70 {};
  71
  72 class COMPHELPER_DLLPUBLIC OSequenceOutputStream final : public OSequenceOutputStream_Base
  73 {
  74 private:
  75     void finalizeOutput();
  76     css::uno::Sequence< sal_Int8 >&                 m_rSequence;
  77     double                                          m_nResizeFactor;
  78     sal_Int32 const                                 m_nMinimumResize;
  79     sal_Int32                                       m_nSize;
  80         // the size of the virtual stream. This is not the size of the sequence, but the number of bytes written
  81         // into the stream at a given moment.
  82
  83     bool                                            m_bConnected;
  84         // closeOutput has been called ?
  85
  86     ::osl::Mutex                                    m_aMutex;
  87
  88     virtual ~OSequenceOutputStream() override { if (m_bConnected) finalizeOutput(); }
  89
  90 public:
  91     /** constructs the object. Everything written into the stream through the XOutputStream methods will be forwarded
  92         to the sequence, reallocating it if necessary. Writing will start at offset 0 within the sequence.
  93         @param      _rSeq               a reference to the sequence which will be used for output.
  94                                         The caller is responsible for taking care of the lifetime of the stream
  95                                         object and the sequence. If you're in doubt about this, use <code>closeOutput</code>
  96                                         before destroying the sequence
  97         @param      _nResizeFactor      the factor which is used for resizing the sequence when necessary. In every
  98                                         resize step, the new sequence size will be calculated by multiplying the current
  99                                         size with this factor, rounded off to the next multiple of 4.
 100         @param      _nMinimumResize     the minimal number of bytes which is additionally allocated on resizing
 101         @see        closeOutput
 102     */
 103     OSequenceOutputStream(
 104         css::uno::Sequence< sal_Int8 >& _rSeq,
 105         double _nResizeFactor = 1.3,
 106         sal_Int32 _nMinimumResize = 128
 107         );
 108
 109     /// same as XOutputStream::writeBytes (as expected :)
 110     virtual void SAL_CALL writeBytes( const css::uno::Sequence< sal_Int8 >& aData ) override;
 111     /// this is a dummy in this implementation, no buffering is used
 112     virtual void SAL_CALL flush(  ) override;
 113     /** closes the output stream. In the case of this class, this means that the sequence used for writing is
 114         resized to the really used size and not used any further, every subsequent call to one of the XOutputStream
 115         methods will throw a <code>NotConnectedException</code>.
 116     */
 117     virtual void SAL_CALL closeOutput(  ) override;
 118 };
 119
 120 } // namespace comphelper
 121
 122 #endif // INCLUDED_COMPHELPER_SEQSTREAM_HXX
 123
 124
 125 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */