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