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 // RCS-ID:      $Id$
   7 // Copyright:   (c) 1998-2001 wxWidgets team
   8 // Licence:     wxWindows licence
   9 ///////////////////////////////////////////////////////////////////////////////
  10
  11 // ============================================================================
  12 // headers
  13 // ============================================================================
  14
  15 #include  "wx/wxprec.h"
  16
  17 #ifdef __BORLANDC__
  18     #pragma hdrstop
  19 #endif  //__BORLANDC__
  20
  21 #ifndef WX_PRECOMP
  22     #include  "wx/string.h"
  23     #include  "wx/intl.h"
  24     #include  "wx/log.h"
  25 #endif
  26
  27 #include "wx/textbuf.h"
  28
  29 // ============================================================================
  30 // wxTextBuffer class implementation
  31 // ============================================================================
  32
  33 // ----------------------------------------------------------------------------
  34 // static methods (always compiled in)
  35 // ----------------------------------------------------------------------------
  36
  37 // default type is the native one
  38 // the native type under Mac OS X is:
  39 //   - Unix when compiling with the Apple Developer Tools (__UNIX__)
  40 //   - Mac when compiling with CodeWarrior (__WXMAC__)
  41
  42 const wxTextFileType wxTextBuffer::typeDefault =
  43 #if defined(__WINDOWS__) || defined(__DOS__) || defined(__PALMOS__)
  44   wxTextFileType_Dos;
  45 #elif defined(__UNIX__)
  46   wxTextFileType_Unix;
  47 #elif defined(__WXMAC__)
  48   wxTextFileType_Mac;
  49 #elif defined(__OS2__)
  50   wxTextFileType_Os2;
  51 #else
  52   wxTextFileType_None;
  53   #error  "wxTextBuffer: unsupported platform."
  54 #endif
  55
  56 const wxChar *wxTextBuffer::GetEOL(wxTextFileType type)
  57 {
  58     switch ( type ) {
  59         default:
  60             wxFAIL_MSG(wxT("bad buffer type in wxTextBuffer::GetEOL."));
  61             // fall through nevertheless - we must return something...
  62
  63         case wxTextFileType_None: return wxEmptyString;
  64         case wxTextFileType_Unix: return wxT("\n");
  65         case wxTextFileType_Dos:  return wxT("\r\n");
  66         case wxTextFileType_Mac:  return wxT("\r");
  67     }
  68 }
  69
  70 wxString wxTextBuffer::Translate(const wxString& text, wxTextFileType type)
  71 {
  72     // don't do anything if there is nothing to do
  73     if ( type == wxTextFileType_None )
  74         return text;
  75
  76     // nor if it is empty
  77     if ( text.empty() )
  78         return text;
  79
  80     wxString eol = GetEOL(type), result;
  81
  82     // optimization: we know that the length of the new string will be about
  83     // the same as the length of the old one, so prealloc memory to aviod
  84     // unnecessary relocations
  85     result.Alloc(text.Len());
  86
  87     wxChar chLast = 0;
  88     for ( const wxChar *pc = text.c_str(); *pc; pc++ )
  89     {
  90         wxChar ch = *pc;
  91         switch ( ch ) {
  92             case _T('\n'):
  93                 // Dos/Unix line termination
  94                 result += eol;
  95                 chLast = 0;
  96                 break;
  97
  98             case _T('\r'):
  99                 if ( chLast == _T('\r') ) {
 100                     // Mac empty line
 101                     result += eol;
 102                 }
 103                 else {
 104                     // just remember it: we don't know whether it is just "\r"
 105                     // or "\r\n" yet
 106                     chLast = _T('\r');
 107                 }
 108                 break;
 109
 110             default:
 111                 if ( chLast == _T('\r') ) {
 112                     // Mac line termination
 113                     result += eol;
 114
 115                     // reset chLast to avoid inserting another eol before the
 116                     // next character
 117                     chLast = 0;
 118                 }
 119
 120                 // add to the current line
 121                 result += ch;
 122         }
 123     }
 124
 125     if ( chLast ) {
 126         // trailing '\r'
 127         result += eol;
 128     }
 129
 130     return result;
 131 }
 132
 133 #if wxUSE_TEXTBUFFER
 134
 135 // ----------------------------------------------------------------------------
 136 // ctors & dtor
 137 // ----------------------------------------------------------------------------
 138
 139 wxTextBuffer::wxTextBuffer(const wxString& strBufferName)
 140             : m_strBufferName(strBufferName)
 141 {
 142     m_nCurLine = 0;
 143     m_isOpened = false;
 144 }
 145
 146 wxTextBuffer::~wxTextBuffer()
 147 {
 148     // required here for Darwin
 149 }
 150
 151 // ----------------------------------------------------------------------------
 152 // buffer operations
 153 // ----------------------------------------------------------------------------
 154
 155 bool wxTextBuffer::Exists() const
 156 {
 157     return OnExists();
 158 }
 159
 160 bool wxTextBuffer::Create(const wxString& strBufferName)
 161 {
 162     m_strBufferName = strBufferName;
 163
 164     return Create();
 165 }
 166
 167 bool wxTextBuffer::Create()
 168 {
 169     // buffer name must be either given in ctor or in Create(const wxString&)
 170     wxASSERT( !m_strBufferName.empty() );
 171
 172     // if the buffer already exists do nothing
 173     if ( Exists() ) return false;
 174
 175     if ( !OnOpen(m_strBufferName, WriteAccess) )
 176         return false;
 177
 178     OnClose();
 179     return true;
 180 }
 181
 182 bool wxTextBuffer::Open(const wxString& strBufferName, wxMBConv& conv)
 183 {
 184     m_strBufferName = strBufferName;
 185
 186     return Open(conv);
 187 }
 188
 189 bool wxTextBuffer::Open(wxMBConv& conv)
 190 {
 191     // buffer name must be either given in ctor or in Open(const wxString&)
 192     wxASSERT( !m_strBufferName.empty() );
 193
 194     // open buffer in read-only mode
 195     if ( !OnOpen(m_strBufferName, ReadAccess) )
 196         return false;
 197
 198     // read buffer into memory
 199     m_isOpened = OnRead(conv);
 200
 201     OnClose();
 202
 203     return m_isOpened;
 204 }
 205
 206 // analyse some lines of the buffer trying to guess it's type.
 207 // if it fails, it assumes the native type for our platform.
 208 wxTextFileType wxTextBuffer::GuessType() const
 209 {
 210     wxASSERT( IsOpened() );
 211
 212     // scan the buffer lines
 213     size_t nUnix = 0,     // number of '\n's alone
 214            nDos  = 0,     // number of '\r\n'
 215            nMac  = 0;     // number of '\r's
 216
 217     // we take MAX_LINES_SCAN in the beginning, middle and the end of buffer
 218     #define MAX_LINES_SCAN    (10)
 219     size_t nCount = m_aLines.Count() / 3,
 220         nScan =  nCount > 3*MAX_LINES_SCAN ? MAX_LINES_SCAN : nCount / 3;
 221
 222     #define   AnalyseLine(n)              \
 223         switch ( m_aTypes[n] ) {            \
 224             case wxTextFileType_Unix: nUnix++; break;   \
 225             case wxTextFileType_Dos:  nDos++;  break;   \
 226             case wxTextFileType_Mac:  nMac++;  break;   \
 227             default: wxFAIL_MSG(_("unknown line terminator")); \
 228         }
 229
 230     size_t n;
 231     for ( n = 0; n < nScan; n++ )     // the beginning
 232         AnalyseLine(n);
 233     for ( n = (nCount - nScan)/2; n < (nCount + nScan)/2; n++ )
 234         AnalyseLine(n);
 235     for ( n = nCount - nScan; n < nCount; n++ )
 236         AnalyseLine(n);
 237
 238     #undef   AnalyseLine
 239
 240     // interpret the results (FIXME far from being even 50% fool proof)
 241     if ( nScan > 0 && nDos + nUnix + nMac == 0 ) {
 242         // no newlines at all
 243         wxLogWarning(_("'%s' is probably a binary buffer."), m_strBufferName.c_str());
 244     }
 245     else {
 246         #define   GREATER_OF(t1, t2) n##t1 == n##t2 ? typeDefault               \
 247                                                 : n##t1 > n##t2             \
 248                                                     ? wxTextFileType_##t1   \
 249                                                     : wxTextFileType_##t2
 250
 251 #if !defined(__WATCOMC__) || wxCHECK_WATCOM_VERSION(1,4)
 252         if ( nDos > nUnix )
 253             return GREATER_OF(Dos, Mac);
 254         else if ( nDos < nUnix )
 255             return GREATER_OF(Unix, Mac);
 256         else {
 257             // nDos == nUnix
 258             return nMac > nDos ? wxTextFileType_Mac : typeDefault;
 259         }
 260 #endif // __WATCOMC__
 261
 262         #undef    GREATER_OF
 263     }
 264
 265     return typeDefault;
 266 }
 267
 268
 269 bool wxTextBuffer::Close()
 270 {
 271     Clear();
 272     m_isOpened = false;
 273
 274     return true;
 275 }
 276
 277 bool wxTextBuffer::Write(wxTextFileType typeNew, wxMBConv& conv)
 278 {
 279     return OnWrite(typeNew, conv);
 280 }
 281
 282 #endif // wxUSE_TEXTBUFFER