include/wx/convauto.h

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/convauto.h
   3 // Purpose:     wxConvAuto class declaration
   4 // Author:      Vadim Zeitlin
   5 // Created:     2006-04-03
   6 // RCS-ID:      $Id$
   7 // Copyright:   (c) 2006 Vadim Zeitlin
   8 // Licence:     wxWindows licence
   9 ///////////////////////////////////////////////////////////////////////////////
  10
  11 #ifndef _WX_CONVAUTO_H_
  12 #define _WX_CONVAUTO_H_
  13
  14 #include "wx/strconv.h"
  15
  16 #if wxUSE_WCHAR_T
  17
  18 // ----------------------------------------------------------------------------
  19 // wxConvAuto: uses BOM to automatically detect input encoding
  20 // ----------------------------------------------------------------------------
  21
  22 class WXDLLIMPEXP_BASE wxConvAuto : public wxMBConv
  23 {
  24 public:
  25     // default ctor, the real conversion will be created on demand
  26     wxConvAuto() { m_conv = NULL; /* the rest will be initialized later */ }
  27
  28     // copy ctor doesn't initialize anything neither as conversion can only be
  29     // deduced on first use
  30     wxConvAuto(const wxConvAuto& WXUNUSED(other)) { m_conv = NULL; }
  31
  32     virtual ~wxConvAuto() { if ( m_conv && m_ownsConv ) delete m_conv; }
  33
  34     // override the base class virtual function(s) to use our m_conv
  35     virtual size_t ToWChar(wchar_t *dst, size_t dstLen,
  36                            const char *src, size_t srcLen = -1) const;
  37
  38     virtual size_t FromWChar(char *dst, size_t dstLen,
  39                              const wchar_t *src, size_t srcLen = -1) const;
  40
  41     virtual size_t GetMBNulLen() const { return m_conv->GetMBNulLen(); }
  42
  43 private:
  44     // all currently recognized BOM values
  45     enum BOMType
  46     {
  47         BOM_None,
  48         BOM_UTF32BE,
  49         BOM_UTF32LE,
  50         BOM_UTF16BE,
  51         BOM_UTF16LE,
  52         BOM_UTF8
  53     };
  54
  55     // return the BOM type of this buffer
  56     static BOMType DetectBOM(const char *src, size_t srcLen);
  57
  58     // initialize m_conv with the conversion to use by default (UTF-8)
  59     void InitWithDefault()
  60     {
  61         m_conv = &wxConvUTF8;
  62         m_ownsConv = false;
  63     }
  64
  65     // create the correct conversion object for the given BOM type
  66     void InitFromBOM(BOMType bomType);
  67
  68     // create the correct conversion object for the BOM present in the
  69     // beginning of the buffer; adjust the buffer to skip the BOM if found
  70     void InitFromInput(const char **src, size_t *len);
  71
  72     // adjust src and len to skip over the BOM (identified by m_bomType) at the
  73     // start of the buffer
  74     void SkipBOM(const char **src, size_t *len) const;
  75
  76
  77     // conversion object which we really use, NULL until the first call to
  78     // either ToWChar() or FromWChar()
  79     wxMBConv *m_conv;
  80
  81     // our BOM type
  82     BOMType m_bomType;
  83
  84     // true if we allocated m_conv ourselves, false if we just use an existing
  85     // global conversion
  86     bool m_ownsConv;
  87
  88     // true if we already skipped BOM when converting (and not just calculating
  89     // the size)
  90     bool m_consumedBOM;
  91
  92
  93     DECLARE_NO_ASSIGN_CLASS(wxConvAuto);
  94 };
  95
  96 #endif // wxUSE_WCHAR_T
  97
  98 #endif // _WX_CONVAUTO_H_
  99