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 // RCS-ID:      $Id$
   8 // Copyright:   (c) 2004 Vadim Zeitlin <vadim@wxwindows.org>
   9 // Licence:     wxWindows licence
  10 ///////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef _WX_SSTREAM_H_
  13 #define _WX_SSTREAM_H_
  14
  15 #include "wx/stream.h"
  16
  17 #if wxUSE_STREAMS
  18
  19 // ----------------------------------------------------------------------------
  20 // wxStringInputStream is a stream reading from the given (fixed size) string
  21 // ----------------------------------------------------------------------------
  22
  23 class WXDLLIMPEXP_BASE wxStringInputStream : public wxInputStream
  24 {
  25 public:
  26     // ctor associates the stream with the given string which makes a copy of
  27     // it
  28     wxStringInputStream(const wxString& s);
  29
  30     virtual wxFileOffset GetLength() const;
  31     virtual bool IsSeekable() const { return true; }
  32
  33 protected:
  34     virtual wxFileOffset OnSysSeek(wxFileOffset ofs, wxSeekMode mode);
  35     virtual wxFileOffset OnSysTell() const;
  36     virtual size_t OnSysRead(void *buffer, size_t size);
  37
  38 private:
  39     // the string that was passed in the ctor
  40     wxString m_str;
  41
  42     // the buffer we're reading from
  43     wxCharBuffer m_buf;
  44
  45     // length of the buffer we're reading from
  46     size_t m_len;
  47
  48     // position in the stream in bytes, *not* in chars
  49     size_t m_pos;
  50
  51     wxDECLARE_NO_COPY_CLASS(wxStringInputStream);
  52 };
  53
  54 // ----------------------------------------------------------------------------
  55 // wxStringOutputStream writes data to the given string, expanding it as needed
  56 // ----------------------------------------------------------------------------
  57
  58 class WXDLLIMPEXP_BASE wxStringOutputStream : public wxOutputStream
  59 {
  60 public:
  61     // The stream will write data either to the provided string or to an
  62     // internal string which can be retrieved using GetString()
  63     //
  64     // Note that the conversion object should have the life time greater than
  65     // this stream.
  66     wxStringOutputStream(wxString *pString = NULL,
  67                          wxMBConv& conv = wxConvUTF8)
  68         : m_conv(conv)
  69 #if wxUSE_UNICODE
  70         , m_unconv(0)
  71 #endif // wxUSE_UNICODE
  72     {
  73         m_str = pString ? pString : &m_strInternal;
  74         m_pos = m_str->length() / sizeof(wxChar);
  75     }
  76
  77     // get the string containing current output
  78     const wxString& GetString() const { return *m_str; }
  79
  80     virtual bool IsSeekable() const { return true; }
  81
  82 protected:
  83     virtual wxFileOffset OnSysTell() const;
  84     virtual size_t OnSysWrite(const void *buffer, size_t size);
  85
  86 private:
  87     // internal string, not used if caller provided his own string
  88     wxString m_strInternal;
  89
  90     // pointer given by the caller or just pointer to m_strInternal
  91     wxString *m_str;
  92
  93     // position in the stream in bytes, *not* in chars
  94     size_t m_pos;
  95
  96     // converter to use: notice that with the default UTF-8 one the input
  97     // stream must contain valid UTF-8 data, use wxConvISO8859_1 to work with
  98     // arbitrary 8 bit data
  99     wxMBConv& m_conv;
 100
 101 #if wxUSE_UNICODE
 102     // unconverted data from the last call to OnSysWrite()
 103     wxMemoryBuffer m_unconv;
 104 #endif // wxUSE_UNICODE
 105
 106     wxDECLARE_NO_COPY_CLASS(wxStringOutputStream);
 107 };
 108
 109 #endif // wxUSE_STREAMS
 110
 111 #endif // _WX_SSTREAM_H_
 112