src/common/sstream.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        common/sstream.cpp
   3 // Purpose:     string-based streams implementation
   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 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 // ----------------------------------------------------------------------------
  17 // headers
  18 // ----------------------------------------------------------------------------
  19
  20 // For compilers that support precompilation, includes "wx.h".
  21 #include "wx/wxprec.h"
  22
  23 #ifdef __BORLANDC__
  24     #pragma hdrstop
  25 #endif
  26
  27 #if wxUSE_STREAMS
  28
  29 #include "wx/sstream.h"
  30
  31 // ============================================================================
  32 // wxStringInputStream implementation
  33 // ============================================================================
  34
  35 // ----------------------------------------------------------------------------
  36 // seek/tell
  37 // ----------------------------------------------------------------------------
  38
  39 off_t wxStringInputStream::OnSysSeek(off_t ofs, wxSeekMode mode)
  40 {
  41     switch ( mode )
  42     {
  43         case wxFromStart:
  44             // nothing to do, ofs already ok
  45             break;
  46
  47         case wxFromEnd:
  48             ofs += m_str.length()*sizeof(wxChar);
  49             break;
  50
  51         case wxFromCurrent:
  52             ofs += m_pos;
  53             break;
  54
  55         default:
  56             wxFAIL_MSG( _T("invalid seek mode") );
  57             return wxInvalidOffset;
  58     }
  59
  60     m_pos = wx_static_cast(size_t, ofs);
  61
  62     return ofs;
  63 }
  64
  65 off_t wxStringInputStream::OnSysTell() const
  66 {
  67     return wx_static_cast(off_t, m_pos);
  68 }
  69
  70 // ----------------------------------------------------------------------------
  71 // actual IO
  72 // ----------------------------------------------------------------------------
  73
  74 size_t wxStringInputStream::OnSysRead(void *buffer, size_t size)
  75 {
  76     const size_t sizeMax = m_str.length()*sizeof(wxChar) - m_pos;
  77
  78     if ( size >= sizeMax )
  79     {
  80         if ( sizeMax == 0 )
  81         {
  82             m_lasterror = wxSTREAM_EOF;
  83             return 0;
  84         }
  85
  86         size = sizeMax;
  87     }
  88
  89     memcpy(buffer, m_str.data() + m_pos, size);
  90     m_pos += size;
  91
  92     return size;
  93 }
  94
  95 // ============================================================================
  96 // wxStringOutputStream implementation
  97 // ============================================================================
  98
  99 // ----------------------------------------------------------------------------
 100 // actual IO
 101 // ----------------------------------------------------------------------------
 102
 103 size_t wxStringOutputStream::OnSysWrite(const void *buffer, size_t size)
 104 {
 105     // in Unicode mode we might not be able to write the last byte
 106     size_t len = size / sizeof(wxChar);
 107
 108     const wxChar *p = wx_static_cast(const wxChar *, buffer);
 109
 110     m_str->Append(wxString(p, p + len + 1));
 111
 112     // return number of bytes actually written
 113     return len*sizeof(wxChar);
 114 }
 115
 116 #endif // wxUSE_STREAMS
 117