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 <config_options.h>
  23 #include <com/sun/star/uno/Sequence.hxx>
  24 #include <com/sun/star/io/XInputStream.hpp>
  25 #include <com/sun/star/io/XOutputStream.hpp>
  26 #include <com/sun/star/io/XSeekable.hpp>
  27 #include <com/sun/star/lang/XUnoTunnel.hpp>
  28 #include <cppuhelper/implbase.hxx>
  29 #include <comphelper/comphelperdllapi.h>
  30 #include <comphelper/bytereader.hxx>
  31 #include <mutex>
  32
  33 namespace comphelper
  34 {
  35
  36 /** Base class for wrappers around memory data that want to be exposed as an XInputStream */
  37 class COMPHELPER_DLLPUBLIC MemoryInputStream
  38     : public ::cppu::WeakImplHelper< css::io::XInputStream, css::io::XSeekable >,
  39       public comphelper::ByteReader
  40 {
  41     std::mutex    m_aMutex;
  42     const sal_Int8* m_pMemoryData;
  43     sal_Int32       m_nMemoryDataLength;
  44     sal_Int32       m_nPos;
  45
  46 public:
  47     MemoryInputStream(const sal_Int8* pData, sal_Int32 nDataLength);
  48
  49 // css::io::XInputStream
  50     virtual sal_Int32 SAL_CALL readBytes( css::uno::Sequence<sal_Int8>& aData, sal_Int32 nBytesToRead ) override;
  51
  52     virtual sal_Int32 SAL_CALL readSomeBytes( css::uno::Sequence<sal_Int8>& aData, sal_Int32 nMaxBytesToRead ) override;
  53
  54     virtual void SAL_CALL skipBytes( sal_Int32 nBytesToSkip ) override;
  55
  56     virtual sal_Int32 SAL_CALL available(  ) override;
  57
  58     virtual void SAL_CALL closeInput(  ) override;
  59
  60     virtual void SAL_CALL seek( sal_Int64 location ) override;
  61     virtual sal_Int64 SAL_CALL getPosition(  ) override;
  62     virtual sal_Int64 SAL_CALL getLength(  ) override;
  63
  64 // comphelper::ByteReader
  65     virtual sal_Int32 readSomeBytes( sal_Int8* pData, sal_Int32 nBytesToRead ) override;
  66
  67 private:
  68     sal_Int32 avail();
  69 };
  70
  71
  72 // Stream for reading data from a sequence of bytes
  73 class COMPHELPER_DLLPUBLIC SequenceInputStream final
  74     : public MemoryInputStream
  75 {
  76     css::uno::Sequence<sal_Int8> const m_aData;
  77
  78 public:
  79     SequenceInputStream(css::uno::Sequence<sal_Int8> const & rData);
  80 };
  81
  82 // don't export to avoid duplicate WeakImplHelper definitions with MSVC
  83 class SAL_DLLPUBLIC_TEMPLATE OSequenceOutputStream_Base
  84     : public ::cppu::WeakImplHelper< css::io::XOutputStream >
  85 {};
  86
  87 class UNLESS_MERGELIBS(COMPHELPER_DLLPUBLIC) OSequenceOutputStream final : public OSequenceOutputStream_Base
  88 {
  89 private:
  90     css::uno::Sequence< sal_Int8 >&                 m_rSequence;
  91     double                                          m_nResizeFactor;
  92     sal_Int32 const                                 m_nMinimumResize;
  93     sal_Int32                                       m_nSize;
  94         // the size of the virtual stream. This is not the size of the sequence, but the number of bytes written
  95         // into the stream at a given moment.
  96
  97     bool                                            m_bConnected;
  98         // closeOutput has been called ?
  99
 100     std::mutex                                      m_aMutex;
 101
 102     void finalizeOutput();
 103     virtual ~OSequenceOutputStream() override { if (m_bConnected) finalizeOutput(); }
 104
 105 public:
 106     /** constructs the object. Everything written into the stream through the XOutputStream methods will be forwarded
 107         to the sequence, reallocating it if necessary. Writing will start at offset 0 within the sequence.
 108         @param      _rSeq               a reference to the sequence which will be used for output.
 109                                         The caller is responsible for taking care of the lifetime of the stream
 110                                         object and the sequence. If you're in doubt about this, use <code>closeOutput</code>
 111                                         before destroying the sequence
 112         @param      _nResizeFactor      the factor which is used for resizing the sequence when necessary. In every
 113                                         resize step, the new sequence size will be calculated by multiplying the current
 114                                         size with this factor, rounded off to the next multiple of 4.
 115         @param      _nMinimumResize     the minimal number of bytes which is additionally allocated on resizing
 116         @see        closeOutput
 117     */
 118     OSequenceOutputStream(
 119         css::uno::Sequence< sal_Int8 >& _rSeq,
 120         double _nResizeFactor = 1.3,
 121         sal_Int32 _nMinimumResize = 128
 122         );
 123
 124     /// same as XOutputStream::writeBytes (as expected :)
 125     virtual void SAL_CALL writeBytes( const css::uno::Sequence< sal_Int8 >& aData ) override;
 126     /// this is a dummy in this implementation, no buffering is used
 127     virtual void SAL_CALL flush(  ) override;
 128     /** closes the output stream. In the case of this class, this means that the sequence used for writing is
 129         resized to the really used size and not used any further, every subsequent call to one of the XOutputStream
 130         methods will throw a <code>NotConnectedException</code>.
 131     */
 132     virtual void SAL_CALL closeOutput(  ) override;
 133 };
 134
 135 } // namespace comphelper
 136
 137 #endif // INCLUDED_COMPHELPER_SEQSTREAM_HXX
 138
 139
 140 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */