xref: /trunk/main/comphelper/inc/comphelper/seqstream.hxx (revision 91144cd0085a7583d2099b982122deb2184ab956)
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21 
22 
23 #ifndef _COMPHELPER_SEQSTREAM_HXX
24 #define _COMPHELPER_SEQSTREAM_HXX
25 
26 #include <com/sun/star/uno/Sequence.hxx>
27 #include <com/sun/star/uno/Reference.hxx>
28 #include <com/sun/star/io/XInputStream.hpp>
29 #include <com/sun/star/io/XOutputStream.hpp>
30 #include <com/sun/star/io/XSeekable.hpp>
31 #include <osl/mutex.hxx>
32 #include <cppuhelper/implbase1.hxx>
33 #include <cppuhelper/implbase2.hxx>
34 #include "comphelper/comphelperdllapi.h"
35 
36 namespace comphelper
37 {
38 
39     typedef ::com::sun::star::uno::Sequence<sal_Int8> ByteSequence;
40 
41 //==================================================================
42 // SequenceInputStream
43 // stream for reading data from a sequence of bytes
44 //==================================================================
45 
46 
47 class COMPHELPER_DLLPUBLIC SequenceInputStream
48 : public ::cppu::WeakImplHelper2< ::com::sun::star::io::XInputStream, ::com::sun::star::io::XSeekable >
49 {
50     ::osl::Mutex    m_aMutex;
51     ByteSequence    m_aData;
52     sal_Int32       m_nPos;
53 
54 public:
55     SequenceInputStream(const ByteSequence& rData);
56 
57 // com::sun::star::io::XInputStream
58     virtual sal_Int32 SAL_CALL readBytes( ::com::sun::star::uno::Sequence<sal_Int8>& aData, sal_Int32 nBytesToRead );
59 
60     virtual sal_Int32 SAL_CALL readSomeBytes( ::com::sun::star::uno::Sequence<sal_Int8>& aData, sal_Int32 nMaxBytesToRead );
61 
62     virtual void SAL_CALL skipBytes( sal_Int32 nBytesToSkip );
63 
64     virtual sal_Int32 SAL_CALL available(  );
65 
66     virtual void SAL_CALL closeInput(  );
67 
68     virtual void SAL_CALL seek( sal_Int64 location );
69     virtual sal_Int64 SAL_CALL getPosition(  );
70     virtual sal_Int64 SAL_CALL getLength(  );
71 
72 private:
73     inline sal_Int32 avail();
74 };
75 typedef ::cppu::WeakImplHelper1< ::com::sun::star::io::XOutputStream > OSequenceOutputStream_Base;
76 
77 class OSequenceOutputStream : public OSequenceOutputStream_Base
78 {
79 protected:
80     ::com::sun::star::uno::Sequence< sal_Int8 >&    m_rSequence;
81     double                                          m_nResizeFactor;
82     sal_Int32                                       m_nMinimumResize;
83     sal_Int32                                       m_nMaximumResize;
84     sal_Int32                                       m_nSize;
85         // the size of the virtual stream. This is not the size of the sequence, but the number of bytes written
86         // into the stream at a given moment.
87 
88     sal_Bool                                        m_bConnected;
89         // closeOutput has been called ?
90 
91     ::osl::Mutex                                    m_aMutex;
92 
93 protected:
~OSequenceOutputStream()94     ~OSequenceOutputStream() { if (m_bConnected) closeOutput(); }
95 
96 public:
97     /** constructs the object. Everything written into the stream through the XOutputStream methods will be forwarded
98         to the sequence, reallocating it if necessary. Writing will start at offset 0 within the sequence.
99         @param      _rSeq               a reference to the sequence which will be used for output.
100                                         The caller is responsible for taking care of the lifetime of the stream
101                                         object and the sequence. If you're in doubt about this, use <code>closeOutput</code>
102                                         before destroying the sequence
103         @param      _nResizeFactor      the factor which is used for resizing the sequence when necessary. In every
104                                         resize step, the new sequence size will be calculated by multiplying the current
105                                         size with this factor, rounded off to the next multiple of 4.
106         @param      _nMinimumResize     the minimal number of bytes which is additionally allocated on resizing
107         @param      _nMaximumResize     as the growth of the stream size is exponential, you may want to specify a
108                                         maxmimum amount of memory which the sequence will grow by. If -1 is used,
109                                         no limit is applied
110         @see        closeOutput
111     */
112     OSequenceOutputStream(
113         ::com::sun::star::uno::Sequence< sal_Int8 >& _rSeq,
114         double _nResizeFactor = 1.3,
115         sal_Int32 _nMinimumResize = 128,
116         sal_Int32 _nMaximumResize = -1
117         );
118 
119     /// same as XOutputStream::writeBytes (as expected :)
120     virtual void SAL_CALL writeBytes( const ::com::sun::star::uno::Sequence< sal_Int8 >& aData );
121     /// this is a dummy in this implementation, no buffering is used
122     virtual void SAL_CALL flush(  );
123     /** closes the output stream. In the case of this class, this means that the sequence used for writing is
124         resized to the really used size and not used any further, every subsequent call to one of the XOutputStream
125         methods will throw a <code>NotConnectedException</code>.
126     */
127     virtual void SAL_CALL closeOutput(  );
128 };
129 
130 } // namespace comphelper
131 
132 #endif //_COMPHELPER_SEQSTREAM_HXX
133