comphelper/source/streaming/seqstream.cxx

   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
  20 #include <comphelper/seqstream.hxx>
  21
  22 #include <osl/diagnose.h>
  23
  24 #include <memory.h>
  25
  26 namespace comphelper
  27 {
  28 using namespace ::com::sun::star::lang;
  29 using namespace ::com::sun::star::io;
  30 using namespace ::com::sun::star::uno;
  31 using namespace ::osl;
  32
  33
  34 // class SequenceInputStream
  35
  36
  37
  38 SequenceInputStream::SequenceInputStream(
  39     css::uno::Sequence<sal_Int8> const & rData)
  40 :   m_aData(rData)
  41 ,   m_nPos(0)
  42 {
  43 }
  44
  45 // checks if closed, returns available size, not mutex-protected
  46
  47 inline sal_Int32 SequenceInputStream::avail()
  48 {
  49     if (m_nPos == -1)
  50         throw NotConnectedException(OUString(), *this);
  51
  52     return m_aData.getLength() - m_nPos;
  53 }
  54
  55 // com::sun::star::io::XInputStream
  56
  57 sal_Int32 SAL_CALL SequenceInputStream::readBytes( Sequence<sal_Int8>& aData, sal_Int32 nBytesToRead )
  58     throw(NotConnectedException, BufferSizeExceededException,
  59           IOException, RuntimeException, std::exception)
  60 {
  61     ::osl::MutexGuard aGuard( m_aMutex );
  62
  63     sal_Int32 nAvail = avail();
  64
  65     if (nBytesToRead < 0)
  66         throw BufferSizeExceededException(OUString(),*this);
  67
  68     if (nAvail < nBytesToRead)
  69         nBytesToRead = nAvail;
  70
  71     aData.realloc(nBytesToRead);
  72     memcpy(aData.getArray(), m_aData.getConstArray() + m_nPos, nBytesToRead);
  73     m_nPos += nBytesToRead;
  74
  75     return nBytesToRead;
  76 }
  77
  78
  79 sal_Int32 SAL_CALL SequenceInputStream::readSomeBytes( Sequence<sal_Int8>& aData, sal_Int32 nMaxBytesToRead )
  80     throw(NotConnectedException, BufferSizeExceededException,
  81           IOException, RuntimeException, std::exception)
  82 {
  83     // all data is available at once
  84     return readBytes(aData, nMaxBytesToRead);
  85 }
  86
  87
  88 void SAL_CALL SequenceInputStream::skipBytes( sal_Int32 nBytesToSkip )
  89     throw(NotConnectedException, BufferSizeExceededException,
  90           IOException, RuntimeException, std::exception)
  91 {
  92     ::osl::MutexGuard aGuard( m_aMutex );
  93
  94     sal_Int32 nAvail = avail();
  95
  96     if (nBytesToSkip < 0)
  97         throw BufferSizeExceededException(OUString(),*this);
  98
  99     if (nAvail < nBytesToSkip)
 100         nBytesToSkip = nAvail;
 101
 102     m_nPos += nBytesToSkip;
 103 }
 104
 105
 106 sal_Int32 SAL_CALL SequenceInputStream::available(  )
 107     throw(NotConnectedException, IOException, RuntimeException, std::exception)
 108 {
 109     ::osl::MutexGuard aGuard( m_aMutex );
 110
 111     return avail();
 112 }
 113
 114
 115 void SAL_CALL SequenceInputStream::closeInput(  )
 116     throw(NotConnectedException, IOException, RuntimeException, std::exception)
 117 {
 118     if (m_nPos == -1)
 119         throw NotConnectedException(OUString(), *this);
 120
 121     m_nPos = -1;
 122 }
 123
 124 void SAL_CALL SequenceInputStream::seek( sal_Int64 location ) throw (IllegalArgumentException, IOException, RuntimeException, std::exception)
 125 {
 126     if ( location > m_aData.getLength() || location < 0 || location > SAL_MAX_INT32 )
 127         throw IllegalArgumentException();
 128     m_nPos = (sal_Int32) location;
 129 }
 130
 131 sal_Int64 SAL_CALL SequenceInputStream::getPosition() throw (IOException, RuntimeException, std::exception)
 132 {
 133     return m_nPos;
 134 }
 135
 136 sal_Int64 SAL_CALL SequenceInputStream::getLength(  ) throw (IOException, RuntimeException, std::exception)
 137 {
 138     return m_aData.getLength();
 139 }
 140
 141
 142 OSequenceOutputStream::OSequenceOutputStream(Sequence< sal_Int8 >& _rSeq, double _nResizeFactor, sal_Int32 _nMinimumResize, sal_Int32 _nMaximumResize)
 143     :m_rSequence(_rSeq)
 144     ,m_nResizeFactor(_nResizeFactor)
 145     ,m_nMinimumResize(_nMinimumResize)
 146     ,m_nMaximumResize(_nMaximumResize)
 147     ,m_nSize(0) // starting at position 0
 148     ,m_bConnected(true)
 149 {
 150     OSL_ENSURE(m_nResizeFactor > 1, "OSequenceOutputStream::OSequenceOutputStream : invalid resize factor !");
 151     OSL_ENSURE((m_nMaximumResize < 0) || (m_nMaximumResize > m_nMinimumResize),
 152         "OSequenceOutputStream::OSequenceOutputStream : these limits don't make any sense !");
 153
 154     if (m_nResizeFactor <= 1)
 155         m_nResizeFactor = 1.3;
 156     if ((m_nMaximumResize >= 0) && (m_nMaximumResize <= m_nMinimumResize))
 157         m_nMaximumResize = m_nMinimumResize * 2;
 158         // this heuristic is as good as any other ... supply better parameters if you don't like it :)
 159 }
 160
 161
 162 void SAL_CALL OSequenceOutputStream::writeBytes( const Sequence< sal_Int8 >& _rData ) throw(NotConnectedException, BufferSizeExceededException, IOException, RuntimeException, std::exception)
 163 {
 164     MutexGuard aGuard(m_aMutex);
 165     if (!m_bConnected)
 166         throw NotConnectedException();
 167
 168     // ensure the sequence has enough space left
 169     if (m_nSize + _rData.getLength() > m_rSequence.getLength())
 170     {
 171         sal_Int32 nCurrentLength = m_rSequence.getLength();
 172         sal_Int32 nNewLength = static_cast< sal_Int32 >(
 173             nCurrentLength * m_nResizeFactor);
 174
 175         if (m_nMinimumResize > nNewLength - nCurrentLength)
 176             // we have a minimum so it's not too inefficient for small sequences and small write requests
 177             nNewLength = nCurrentLength + m_nMinimumResize;
 178
 179         if ((m_nMaximumResize > 0) && (nNewLength - nCurrentLength > m_nMaximumResize))
 180             // such a large step is not allowed
 181             nNewLength = nCurrentLength + m_nMaximumResize;
 182
 183         if (nNewLength < m_nSize + _rData.getLength())
 184         {   // it's not enough .... the data would not fit
 185
 186             // let's take the double amount of the length of the data to be written, as the next write
 187             // request could be as large as this one
 188             sal_Int32 nNewGrowth = _rData.getLength() * 2;
 189             if ((m_nMaximumResize > 0) && (nNewGrowth > m_nMaximumResize))
 190             {   // we came to the limit, again ...
 191                 nNewGrowth = m_nMaximumResize;
 192                 if (nNewGrowth + nCurrentLength < m_nSize + _rData.getLength())
 193                     // but it would not fit if we respect the limit
 194                     nNewGrowth = m_nSize + _rData.getLength() - nCurrentLength;
 195             }
 196             nNewLength = nCurrentLength + nNewGrowth;
 197         }
 198
 199         // round it off to the next multiple of 4 ...
 200         nNewLength = (nNewLength + 3) / 4 * 4;
 201
 202         m_rSequence.realloc(nNewLength);
 203     }
 204
 205     OSL_ENSURE(m_rSequence.getLength() >= m_nSize + _rData.getLength(),
 206         "ooops ... the realloc algorithm seems to be wrong :( !");
 207
 208     memcpy(m_rSequence.getArray() + m_nSize, _rData.getConstArray(), _rData.getLength());
 209     m_nSize += _rData.getLength();
 210 }
 211
 212
 213 void SAL_CALL OSequenceOutputStream::flush(  ) throw(NotConnectedException, BufferSizeExceededException, IOException, RuntimeException, std::exception)
 214 {
 215     MutexGuard aGuard(m_aMutex);
 216     if (!m_bConnected)
 217         throw NotConnectedException();
 218
 219     // cut the sequence to the real size
 220     m_rSequence.realloc(m_nSize);
 221 }
 222
 223
 224 void SAL_CALL OSequenceOutputStream::closeOutput(  ) throw(NotConnectedException, BufferSizeExceededException, IOException, RuntimeException, std::exception)
 225 {
 226     MutexGuard aGuard(m_aMutex);
 227     if (!m_bConnected)
 228         throw NotConnectedException();
 229
 230     // cut the sequence to the real size
 231     m_rSequence.realloc(m_nSize);
 232     // and don't allow any further accesses
 233     m_bConnected = false;
 234 }
 235
 236 } // namespace comphelper
 237
 238 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */