1 // Created on: 2001-10-01
2 // Created by: Julia DOROVSKIKH
3 // Copyright (c) 2001-2014 OPEN CASCADE SAS
5 // This file is part of Open CASCADE Technology software library.
7 // This library is free software; you can redistribute it and/or modify it under
8 // the terms of the GNU Lesser General Public License version 2.1 as published
9 // by the Free Software Foundation, with special exception defined in the file
10 // OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
11 // distribution for complete text of the license and disclaimer of any warranty.
13 // Alternatively, this file may be used under the terms of Open CASCADE
14 // commercial license or contractual agreement.
16 #ifndef LDOM_OSStream_HeaderFile
17 #define LDOM_OSStream_HeaderFile
19 // This implementation allows to increase performance
20 // of outputting data into a string
21 // avoiding reallocation of buffer.
22 // class LDOM_OSStream implements output into a sequence of
23 // strings and getting the result as a string.
24 // It inherits Standard_OStream (ostream).
25 // Beside methods of ostream, it also has additional
26 // useful methods: str(), Length() and Clear().
27 // struct LDOM_StringElem is one element of internal sequence
28 // class LDOM_SBuffer inherits streambuf and
29 // redefines some virtual methods of it
30 // (overflow() and xsputn())
31 // This class contains pointers on first
32 // and current element of sequence,
33 // also it has methods for the sequence management.
35 #include <NCollection_DefineAlloc.hxx>
36 #include <NCollection_BaseAllocator.hxx>
37 #include <Standard_OStream.hxx>
38 #include <Standard_Boolean.hxx>
41 #include <stdio.h> /* EOF */
43 class LDOM_SBuffer : public streambuf
45 // One element of sequence.
46 // Can only be allocated by the allocator and assumes
47 // it is IncAllocator, so destructor isn't required.
48 struct LDOM_StringElem
50 char* buf; //!< pointer on data string
51 int len; //!< quantity of really written data
52 LDOM_StringElem* next; //!< pointer on the next element of a sequence
54 DEFINE_NCOLLECTION_ALLOC
56 LDOM_StringElem(const int, const Handle(NCollection_BaseAllocator)&);
60 LDOM_StringElem (const LDOM_StringElem&);
61 LDOM_StringElem& operator= (const LDOM_StringElem&);
65 Standard_EXPORT LDOM_SBuffer (const Standard_Integer theMaxBuf);
66 // Constructor. Sets a default value for the
67 // length of each sequence element.
69 Standard_EXPORT Standard_CString str () const;
70 // Concatenates strings of all sequence elements
71 // into one string. Space for output string is allocated
73 // Caller of this function is responsible
74 // for memory release after the string usage.
76 Standard_Integer Length () const {return myLength;}
77 // Returns full length of data contained
79 Standard_EXPORT void Clear ();
80 // Clears first element of sequence and removes all others
82 // Methods of streambuf
84 Standard_EXPORT virtual int overflow(int c = EOF);
85 Standard_EXPORT virtual int underflow();
86 //virtual int uflow();
88 Standard_EXPORT virtual int xsputn(const char* s, int n);
89 //virtual int xsgetn(char* s, int n);
92 Standard_EXPORT ~LDOM_SBuffer ();
97 Standard_Integer myMaxBuf; // default length of one element
98 Standard_Integer myLength; // full length of contained data
99 LDOM_StringElem* myFirstString; // the head of the sequence
100 LDOM_StringElem* myCurString; // current element of the sequence
101 Handle(NCollection_BaseAllocator) myAlloc; //allocator for chunks
104 class LDOM_OSStream : public Standard_OStream
107 Standard_EXPORT LDOM_OSStream (const Standard_Integer theMaxBuf);
110 Standard_CString str () const {return myBuffer.str();}
112 Standard_Integer Length () const {return myBuffer.Length();}
114 void Clear () { myBuffer.Clear(); }
117 LDOM_SBuffer myBuffer;