include/wx/sstream.h

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/sstream.h
   3 // Purpose:     string-based streams
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     2004-09-19
   7 // Copyright:   (c) 2004 Vadim Zeitlin <vadim@wxwindows.org>
   8 // Licence:     wxWindows licence
   9 ///////////////////////////////////////////////////////////////////////////////
  10
  11 #ifndef _WX_SSTREAM_H_
  12 #define _WX_SSTREAM_H_
  13
  14 #include "wx/stream.h"
  15
  16 #if wxUSE_STREAMS
  17
  18 // ----------------------------------------------------------------------------
  19 // wxStringInputStream is a stream reading from the given (fixed size) string
  20 // ----------------------------------------------------------------------------
  21
  22 class WXDLLIMPEXP_BASE wxStringInputStream : public wxInputStream
  23 {
  24 public:
  25     // ctor associates the stream with the given string which makes a copy of
  26     // it
  27     wxStringInputStream(const wxString& s);
  28
  29     virtual wxFileOffset GetLength() const;
  30     virtual bool IsSeekable() const { return true; }
  31
  32 protected:
  33     virtual wxFileOffset OnSysSeek(wxFileOffset ofs, wxSeekMode mode);
  34     virtual wxFileOffset OnSysTell() const;
  35     virtual size_t OnSysRead(void *buffer, size_t size);
  36
  37 private:
  38     // the string that was passed in the ctor
  39     wxString m_str;
  40
  41     // the buffer we're reading from
  42     wxCharBuffer m_buf;
  43
  44     // length of the buffer we're reading from
  45     size_t m_len;
  46
  47     // position in the stream in bytes, *not* in chars
  48     size_t m_pos;
  49
  50     wxDECLARE_NO_COPY_CLASS(wxStringInputStream);
  51 };
  52
  53 // ----------------------------------------------------------------------------
  54 // wxStringOutputStream writes data to the given string, expanding it as needed
  55 // ----------------------------------------------------------------------------
  56
  57 class WXDLLIMPEXP_BASE wxStringOutputStream : public wxOutputStream
  58 {
  59 public:
  60     // The stream will write data either to the provided string or to an
  61     // internal string which can be retrieved using GetString()
  62     //
  63     // Note that the conversion object should have the life time greater than
  64     // this stream.
  65     wxStringOutputStream(wxString *pString = NULL,
  66                          wxMBConv& conv = wxConvUTF8)
  67         : m_conv(conv)
  68 #if wxUSE_UNICODE
  69         , m_unconv(0)
  70 #endif // wxUSE_UNICODE
  71     {
  72         m_str = pString ? pString : &m_strInternal;
  73         m_pos = m_str->length() / sizeof(wxChar);
  74     }
  75
  76     // get the string containing current output
  77     const wxString& GetString() const { return *m_str; }
  78
  79     virtual bool IsSeekable() const { return true; }
  80
  81 protected:
  82     virtual wxFileOffset OnSysTell() const;
  83     virtual size_t OnSysWrite(const void *buffer, size_t size);
  84
  85 private:
  86     // internal string, not used if caller provided his own string
  87     wxString m_strInternal;
  88
  89     // pointer given by the caller or just pointer to m_strInternal
  90     wxString *m_str;
  91
  92     // position in the stream in bytes, *not* in chars
  93     size_t m_pos;
  94
  95     // converter to use: notice that with the default UTF-8 one the input
  96     // stream must contain valid UTF-8 data, use wxConvISO8859_1 to work with
  97     // arbitrary 8 bit data
  98     wxMBConv& m_conv;
  99
 100 #if wxUSE_UNICODE
 101     // unconverted data from the last call to OnSysWrite()
 102     wxMemoryBuffer m_unconv;
 103 #endif // wxUSE_UNICODE
 104
 105     wxDECLARE_NO_COPY_CLASS(wxStringOutputStream);
 106 };
 107
 108 #endif // wxUSE_STREAMS
 109
 110 #endif // _WX_SSTREAM_H_
 111