xref: /trunk/main/comphelper/source/streaming/seqstream.cxx (revision 91144cd0085a7583d2099b982122deb2184ab956)
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21 
22 
23 
24 // MARKER(update_precomp.py): autogen include statement, do not remove
25 #include "precompiled_comphelper.hxx"
26 #include <comphelper/seqstream.hxx>
27 
28 #include <memory.h> // for memcpy
29 
30 namespace comphelper
31 {
32 using namespace ::com::sun::star::lang;
33 using namespace ::com::sun::star::io;
34 using namespace ::com::sun::star::uno;
35 using namespace ::osl;
36 
37 //---------------------------------------------------------------------------------------------
38 // class SequenceInputStream
39 //---------------------------------------------------------------------------------------------
40 
41 //------------------------------------------------------------------
SequenceInputStream(const ByteSequence & rData)42 SequenceInputStream::SequenceInputStream(const ByteSequence& rData)
43 :   m_aData(rData)
44 ,   m_nPos(0)
45 {
46 }
47 
48 // checks if closed, returns available size, not mutex-protected
49 //------------------------------------------------------------------
avail()50 inline sal_Int32 SequenceInputStream::avail()
51 {
52     if (m_nPos == -1)
53         throw NotConnectedException(::rtl::OUString(), *this);
54 
55     return m_aData.getLength() - m_nPos;
56 }
57 
58 // com::sun::star::io::XInputStream
59 //------------------------------------------------------------------
readBytes(Sequence<sal_Int8> & aData,sal_Int32 nBytesToRead)60 sal_Int32 SAL_CALL SequenceInputStream::readBytes( Sequence<sal_Int8>& aData, sal_Int32 nBytesToRead )
61 {
62     ::osl::MutexGuard aGuard( m_aMutex );
63 
64     sal_Int32 nAvail = avail();
65 
66     if (nBytesToRead < 0)
67         throw BufferSizeExceededException(::rtl::OUString(),*this);
68 
69     if (nAvail < nBytesToRead)
70         nBytesToRead = nAvail;
71 
72     aData.realloc(nBytesToRead);
73     memcpy(aData.getArray(), m_aData.getConstArray() + m_nPos, nBytesToRead);
74     m_nPos += nBytesToRead;
75 
76     return nBytesToRead;
77 }
78 
79 //------------------------------------------------------------------
readSomeBytes(Sequence<sal_Int8> & aData,sal_Int32 nMaxBytesToRead)80 sal_Int32 SAL_CALL SequenceInputStream::readSomeBytes( Sequence<sal_Int8>& aData, sal_Int32 nMaxBytesToRead )
81 {
82     // all data is available at once
83     return readBytes(aData, nMaxBytesToRead);
84 }
85 
86 //------------------------------------------------------------------
skipBytes(sal_Int32 nBytesToSkip)87 void SAL_CALL SequenceInputStream::skipBytes( sal_Int32 nBytesToSkip )
88 {
89     ::osl::MutexGuard aGuard( m_aMutex );
90 
91     sal_Int32 nAvail = avail();
92 
93     if (nBytesToSkip < 0)
94         throw BufferSizeExceededException(::rtl::OUString(),*this);
95 
96     if (nAvail < nBytesToSkip)
97         nBytesToSkip = nAvail;
98 
99     m_nPos += nBytesToSkip;
100 }
101 
102 //------------------------------------------------------------------
available()103 sal_Int32 SAL_CALL SequenceInputStream::available(  )
104 {
105     ::osl::MutexGuard aGuard( m_aMutex );
106 
107     return avail();
108 }
109 
110 //------------------------------------------------------------------
closeInput()111 void SAL_CALL SequenceInputStream::closeInput(  )
112 {
113     if (m_nPos == -1)
114         throw NotConnectedException(::rtl::OUString(), *this);
115 
116     m_nPos = -1;
117 }
118 
seek(sal_Int64 location)119 void SAL_CALL SequenceInputStream::seek( sal_Int64 location )
120 {
121     if ( location > m_aData.getLength() || location < 0 || location > SAL_MAX_INT32 )
122         throw IllegalArgumentException();
123     m_nPos = (sal_Int32) location;
124 }
125 
getPosition()126 sal_Int64 SAL_CALL SequenceInputStream::getPosition()
127 {
128     return m_nPos;
129 }
130 
getLength()131 sal_Int64 SAL_CALL SequenceInputStream::getLength(  )
132 {
133     return m_aData.getLength();
134 }
135 
136 //--------------------------------------------------------------------------
OSequenceOutputStream(Sequence<sal_Int8> & _rSeq,double _nResizeFactor,sal_Int32 _nMinimumResize,sal_Int32 _nMaximumResize)137 OSequenceOutputStream::OSequenceOutputStream(Sequence< sal_Int8 >& _rSeq, double _nResizeFactor, sal_Int32 _nMinimumResize, sal_Int32 _nMaximumResize)
138     :m_rSequence(_rSeq)
139     ,m_nResizeFactor(_nResizeFactor)
140     ,m_nMinimumResize(_nMinimumResize)
141     ,m_nMaximumResize(_nMaximumResize)
142     ,m_nSize(0) // starting at position 0
143     ,m_bConnected(sal_True)
144 {
145     OSL_ENSURE(m_nResizeFactor > 1, "OSequenceOutputStream::OSequenceOutputStream : invalid resize factor !");
146     OSL_ENSURE((m_nMaximumResize < 0) || (m_nMaximumResize > m_nMinimumResize),
147         "OSequenceOutputStream::OSequenceOutputStream : these limits don't make any sense !");
148 
149     if (m_nResizeFactor <= 1)
150         m_nResizeFactor = 1.3;
151     if ((m_nMaximumResize >= 0) && (m_nMaximumResize <= m_nMinimumResize))
152         m_nMaximumResize = m_nMinimumResize * 2;
153         // this heuristic is as good as any other ... supply better parameters if you don't like it :)
154 }
155 
156 //--------------------------------------------------------------------------
writeBytes(const Sequence<sal_Int8> & _rData)157 void SAL_CALL OSequenceOutputStream::writeBytes( const Sequence< sal_Int8 >& _rData )
158 {
159     MutexGuard aGuard(m_aMutex);
160     if (!m_bConnected)
161         throw NotConnectedException();
162 
163     // ensure the sequence has enoungh space left
164     if (m_nSize + _rData.getLength() > m_rSequence.getLength())
165     {
166         sal_Int32 nCurrentLength = m_rSequence.getLength();
167         sal_Int32 nNewLength = static_cast< sal_Int32 >(
168             nCurrentLength * m_nResizeFactor);
169 
170         if (m_nMinimumResize > nNewLength - nCurrentLength)
171             // we have a minimum so it's not too inefficient for small sequences and small write requests
172             nNewLength = nCurrentLength + m_nMinimumResize;
173 
174         if ((m_nMaximumResize > 0) && (nNewLength - nCurrentLength > m_nMaximumResize))
175             // such a large step is not allowed
176             nNewLength = nCurrentLength + m_nMaximumResize;
177 
178         if (nNewLength < m_nSize + _rData.getLength())
179         {   // it's not enough .... the data would not fit
180 
181             // let's take the double amount of the length of the data to be written, as the next write
182             // request could be as large as this one
183             sal_Int32 nNewGrowth = _rData.getLength() * 2;
184             if ((m_nMaximumResize > 0) && (nNewGrowth > m_nMaximumResize))
185             {   // we came to the limit, again ...
186                 nNewGrowth = m_nMaximumResize;
187                 if (nNewGrowth + nCurrentLength < m_nSize + _rData.getLength())
188                     // but it would not fit if we respect the limit
189                     nNewGrowth = m_nSize + _rData.getLength() - nCurrentLength;
190             }
191             nNewLength = nCurrentLength + nNewGrowth;
192         }
193 
194         // round it off to the next multiple of 4 ...
195         nNewLength = (nNewLength + 3) / 4 * 4;
196 
197         m_rSequence.realloc(nNewLength);
198     }
199 
200     OSL_ENSURE(m_rSequence.getLength() >= m_nSize + _rData.getLength(),
201         "ooops ... the realloc algorithm seems to be wrong :( !");
202 
203     memcpy(m_rSequence.getArray() + m_nSize, _rData.getConstArray(), _rData.getLength());
204     m_nSize += _rData.getLength();
205 }
206 
207 //--------------------------------------------------------------------------
flush()208 void SAL_CALL OSequenceOutputStream::flush(  )
209 {
210     MutexGuard aGuard(m_aMutex);
211     if (!m_bConnected)
212         throw NotConnectedException();
213 
214     // cut the sequence to the real size
215     m_rSequence.realloc(m_nSize);
216 }
217 
218 //--------------------------------------------------------------------------
closeOutput()219 void SAL_CALL OSequenceOutputStream::closeOutput(  )
220 {
221     MutexGuard aGuard(m_aMutex);
222     if (!m_bConnected)
223         throw NotConnectedException();
224 
225     // cut the sequence to the real size
226     m_rSequence.realloc(m_nSize);
227     // and don't allow any further accesses
228     m_bConnected = sal_False;
229 }
230 
231 } // namespace comphelper
232