src/common/textbuf.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/common/textbuf.cpp
   3 // Purpose:     implementation of wxTextBuffer class
   4 // Created:     14.11.01
   5 // Author:      Morten Hanssen, Vadim Zeitlin
   6 // Copyright:   (c) 1998-2001 wxWidgets team
   7 // Licence:     wxWindows licence
   8 ///////////////////////////////////////////////////////////////////////////////
   9
  10 // ============================================================================
  11 // headers
  12 // ============================================================================
  13
  14 #include  "wx/wxprec.h"
  15
  16 #ifdef __BORLANDC__
  17     #pragma hdrstop
  18 #endif  //__BORLANDC__
  19
  20 #ifndef WX_PRECOMP
  21     #include  "wx/string.h"
  22     #include  "wx/intl.h"
  23     #include  "wx/log.h"
  24 #endif
  25
  26 #include "wx/textbuf.h"
  27
  28 // ============================================================================
  29 // wxTextBuffer class implementation
  30 // ============================================================================
  31
  32 // ----------------------------------------------------------------------------
  33 // static methods (always compiled in)
  34 // ----------------------------------------------------------------------------
  35
  36 // default type is the native one
  37
  38 const wxTextFileType wxTextBuffer::typeDefault =
  39 #if defined(__WINDOWS__) || defined(__DOS__)
  40   wxTextFileType_Dos;
  41 #elif defined(__UNIX__)
  42   wxTextFileType_Unix;
  43 #elif defined(__OS2__)
  44   wxTextFileType_Os2;
  45 #else
  46   wxTextFileType_None;
  47   #error  "wxTextBuffer: unsupported platform."
  48 #endif
  49
  50 const wxChar *wxTextBuffer::GetEOL(wxTextFileType type)
  51 {
  52     switch ( type ) {
  53         default:
  54             wxFAIL_MSG(wxT("bad buffer type in wxTextBuffer::GetEOL."));
  55             // fall through nevertheless - we must return something...
  56
  57         case wxTextFileType_None: return wxEmptyString;
  58         case wxTextFileType_Unix: return wxT("\n");
  59         case wxTextFileType_Dos:  return wxT("\r\n");
  60         case wxTextFileType_Mac:  return wxT("\r");
  61     }
  62 }
  63
  64 wxString wxTextBuffer::Translate(const wxString& text, wxTextFileType type)
  65 {
  66     // don't do anything if there is nothing to do
  67     if ( type == wxTextFileType_None )
  68         return text;
  69
  70     // nor if it is empty
  71     if ( text.empty() )
  72         return text;
  73
  74     wxString eol = GetEOL(type), result;
  75
  76     // optimization: we know that the length of the new string will be about
  77     // the same as the length of the old one, so prealloc memory to avoid
  78     // unnecessary relocations
  79     result.Alloc(text.Len());
  80
  81     wxChar chLast = 0;
  82     for ( wxString::const_iterator i = text.begin(); i != text.end(); ++i )
  83     {
  84         wxChar ch = *i;
  85         switch ( ch ) {
  86             case wxT('\n'):
  87                 // Dos/Unix line termination
  88                 result += eol;
  89                 chLast = 0;
  90                 break;
  91
  92             case wxT('\r'):
  93                 if ( chLast == wxT('\r') ) {
  94                     // Mac empty line
  95                     result += eol;
  96                 }
  97                 else {
  98                     // just remember it: we don't know whether it is just "\r"
  99                     // or "\r\n" yet
 100                     chLast = wxT('\r');
 101                 }
 102                 break;
 103
 104             default:
 105                 if ( chLast == wxT('\r') ) {
 106                     // Mac line termination
 107                     result += eol;
 108
 109                     // reset chLast to avoid inserting another eol before the
 110                     // next character
 111                     chLast = 0;
 112                 }
 113
 114                 // add to the current line
 115                 result += ch;
 116         }
 117     }
 118
 119     if ( chLast ) {
 120         // trailing '\r'
 121         result += eol;
 122     }
 123
 124     return result;
 125 }
 126
 127 #if wxUSE_TEXTBUFFER
 128
 129 wxString wxTextBuffer::ms_eof;
 130
 131 // ----------------------------------------------------------------------------
 132 // ctors & dtor
 133 // ----------------------------------------------------------------------------
 134
 135 wxTextBuffer::wxTextBuffer(const wxString& strBufferName)
 136             : m_strBufferName(strBufferName)
 137 {
 138     m_nCurLine = 0;
 139     m_isOpened = false;
 140 }
 141
 142 wxTextBuffer::~wxTextBuffer()
 143 {
 144     // required here for Darwin
 145 }
 146
 147 // ----------------------------------------------------------------------------
 148 // buffer operations
 149 // ----------------------------------------------------------------------------
 150
 151 bool wxTextBuffer::Exists() const
 152 {
 153     return OnExists();
 154 }
 155
 156 bool wxTextBuffer::Create(const wxString& strBufferName)
 157 {
 158     m_strBufferName = strBufferName;
 159
 160     return Create();
 161 }
 162
 163 bool wxTextBuffer::Create()
 164 {
 165     // buffer name must be either given in ctor or in Create(const wxString&)
 166     wxASSERT( !m_strBufferName.empty() );
 167
 168     // if the buffer already exists do nothing
 169     if ( Exists() ) return false;
 170
 171     if ( !OnOpen(m_strBufferName, WriteAccess) )
 172         return false;
 173
 174     OnClose();
 175     return true;
 176 }
 177
 178 bool wxTextBuffer::Open(const wxString& strBufferName, const wxMBConv& conv)
 179 {
 180     m_strBufferName = strBufferName;
 181
 182     return Open(conv);
 183 }
 184
 185 bool wxTextBuffer::Open(const wxMBConv& conv)
 186 {
 187     // buffer name must be either given in ctor or in Open(const wxString&)
 188     wxASSERT( !m_strBufferName.empty() );
 189
 190     // open buffer in read-only mode
 191     if ( !OnOpen(m_strBufferName, ReadAccess) )
 192         return false;
 193
 194     // read buffer into memory
 195     m_isOpened = OnRead(conv);
 196
 197     OnClose();
 198
 199     return m_isOpened;
 200 }
 201
 202 // analyse some lines of the buffer trying to guess it's type.
 203 // if it fails, it assumes the native type for our platform.
 204 wxTextFileType wxTextBuffer::GuessType() const
 205 {
 206     wxASSERT( IsOpened() );
 207
 208     // scan the buffer lines
 209     size_t nUnix = 0,     // number of '\n's alone
 210            nDos  = 0,     // number of '\r\n'
 211            nMac  = 0;     // number of '\r's
 212
 213     // we take MAX_LINES_SCAN in the beginning, middle and the end of buffer
 214     #define MAX_LINES_SCAN    (10)
 215     size_t nCount = m_aLines.GetCount() / 3,
 216         nScan =  nCount > 3*MAX_LINES_SCAN ? MAX_LINES_SCAN : nCount / 3;
 217
 218     #define   AnalyseLine(n)              \
 219         switch ( m_aTypes[n] ) {            \
 220             case wxTextFileType_Unix: nUnix++; break;   \
 221             case wxTextFileType_Dos:  nDos++;  break;   \
 222             case wxTextFileType_Mac:  nMac++;  break;   \
 223             default: wxFAIL_MSG(wxT("unknown line terminator")); \
 224         }
 225
 226     size_t n;
 227     for ( n = 0; n < nScan; n++ )     // the beginning
 228         AnalyseLine(n);
 229     for ( n = (nCount - nScan)/2; n < (nCount + nScan)/2; n++ )
 230         AnalyseLine(n);
 231     for ( n = nCount - nScan; n < nCount; n++ )
 232         AnalyseLine(n);
 233
 234     #undef   AnalyseLine
 235
 236     // interpret the results (FIXME far from being even 50% fool proof)
 237     if ( nScan > 0 && nDos + nUnix + nMac == 0 ) {
 238         // no newlines at all
 239         wxLogWarning(_("'%s' is probably a binary buffer."), m_strBufferName.c_str());
 240     }
 241     else {
 242         #define   GREATER_OF(t1, t2) n##t1 == n##t2 ? typeDefault               \
 243                                                 : n##t1 > n##t2             \
 244                                                     ? wxTextFileType_##t1   \
 245                                                     : wxTextFileType_##t2
 246
 247 #if !defined(__WATCOMC__) || wxCHECK_WATCOM_VERSION(1,4)
 248         if ( nDos > nUnix )
 249             return GREATER_OF(Dos, Mac);
 250         else if ( nDos < nUnix )
 251             return GREATER_OF(Unix, Mac);
 252         else {
 253             // nDos == nUnix
 254             return nMac > nDos ? wxTextFileType_Mac : typeDefault;
 255         }
 256 #endif // __WATCOMC__
 257
 258         #undef    GREATER_OF
 259     }
 260
 261     return typeDefault;
 262 }
 263
 264
 265 bool wxTextBuffer::Close()
 266 {
 267     Clear();
 268     m_isOpened = false;
 269
 270     return true;
 271 }
 272
 273 bool wxTextBuffer::Write(wxTextFileType typeNew, const wxMBConv& conv)
 274 {
 275     return OnWrite(typeNew, conv);
 276 }
 277
 278 #endif // wxUSE_TEXTBUFFER