src/common/textfile.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        textfile.cpp
   3 // Purpose:     implementation of wxTextFile class
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     03.04.98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 1998 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
   9 // Licence:     wxWindows license
  10 ///////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // headers
  14 // ============================================================================
  15
  16 #ifdef __GNUG__
  17     #pragma implementation "textfile.h"
  18 #endif
  19
  20 #include  "wx/wxprec.h"
  21
  22 #ifdef    __BORLANDC__
  23     #pragma hdrstop
  24 #endif  //__BORLANDC__
  25
  26 #if !wxUSE_FILE
  27     #undef wxUSE_TEXTFILE
  28     #define wxUSE_TEXTFILE 0
  29 #endif // wxUSE_FILE
  30
  31 #ifndef WX_PRECOMP
  32     #include  "wx/string.h"
  33     #include  "wx/intl.h"
  34     #include  "wx/file.h"
  35     #include  "wx/log.h"
  36 #endif
  37
  38 #include  "wx/textfile.h"
  39
  40 // ============================================================================
  41 // wxTextFile class implementation
  42 // ============================================================================
  43
  44 // ----------------------------------------------------------------------------
  45 // static methods (always compiled in)
  46 // ----------------------------------------------------------------------------
  47
  48 // default type is the native one
  49 const wxTextFileType wxTextFile::typeDefault =
  50 #if   defined(__WINDOWS__)
  51   wxTextFileType_Dos;
  52 #elif defined(__UNIX__)
  53   wxTextFileType_Unix;
  54 #elif defined(__WXMAC__)
  55   wxTextFileType_Mac;
  56 #elif defined(__WXPM__)
  57   wxTextFileType_Os2;
  58 #else
  59   wxTextFileType_None;
  60   #error  "wxTextFile: unsupported platform."
  61 #endif
  62
  63 const wxChar *wxTextFile::GetEOL(wxTextFileType type)
  64 {
  65     switch ( type ) {
  66       default:
  67         wxFAIL_MSG(T("bad file type in wxTextFile::GetEOL."));
  68         // fall through nevertheless - we must return something...
  69
  70       case wxTextFileType_None: return T("");
  71       case wxTextFileType_Unix: return T("\n");
  72       case wxTextFileType_Dos:  return T("\r\n");
  73       case wxTextFileType_Mac:  return T("\r");
  74     }
  75 }
  76
  77
  78 wxString wxTextFile::Translate(const wxString& text, wxTextFileType type)
  79 {
  80     // don't do anything if there is nothing to do
  81     if ( type == wxTextFileType_None )
  82         return text;
  83
  84     wxString eol = GetEOL(type), result;
  85
  86     // optimization: we know that the length of the new string will be about
  87     // the same as the length of the old one, so prealloc memory to aviod
  88     // unnecessary relocations
  89     result.Alloc(text.Len());
  90
  91     wxChar chLast = 0;
  92     for ( const wxChar *pc = text.c_str(); *pc; pc++ )
  93     {
  94         wxChar ch = *pc;
  95         switch ( ch ) {
  96             case '\n':
  97                 // Dos/Unix line termination
  98                 result += eol;
  99                 chLast = '\n';
 100                 break;
 101
 102             case '\r':
 103                 if ( chLast == '\r' ) {
 104                     // Mac empty line
 105                     result += eol;
 106                 }
 107                 else
 108                     chLast = '\r';
 109                 break;
 110
 111             default:
 112                 if ( chLast == '\r' ) {
 113                     // Mac line termination
 114                     result += eol;
 115                     chLast = ch;
 116                 }
 117                 else {
 118                     // add to the current line
 119                     result += ch;
 120                 }
 121         }
 122     }
 123
 124     return result;
 125 }
 126
 127 #if wxUSE_TEXTFILE
 128
 129 // ----------------------------------------------------------------------------
 130 // ctors & dtor
 131 // ----------------------------------------------------------------------------
 132
 133 wxTextFile::wxTextFile(const wxString& strFile) : m_strFile(strFile)
 134 {
 135   m_nCurLine = 0;
 136   m_isOpened = FALSE;
 137 }
 138
 139 wxTextFile::~wxTextFile()
 140 {
 141   // m_file dtor called automatically
 142 }
 143
 144 // ----------------------------------------------------------------------------
 145 // file operations
 146 // ----------------------------------------------------------------------------
 147
 148 bool wxTextFile::Open(const wxString& strFile)
 149 {
 150   m_strFile = strFile;
 151
 152   return Open();
 153 }
 154
 155 bool wxTextFile::Open()
 156 {
 157   // file name must be either given in ctor or in Open(const wxString&)
 158   wxASSERT( !m_strFile.IsEmpty() );
 159
 160   // open file in read-only mode
 161   if ( !m_file.Open(m_strFile) )
 162     return FALSE;
 163
 164   // read file into memory
 165   m_isOpened = Read();
 166
 167   m_file.Close();
 168
 169   return m_isOpened;
 170 }
 171
 172 // analyse some lines of the file trying to guess it's type.
 173 // if it fails, it assumes the native type for our platform.
 174 wxTextFileType wxTextFile::GuessType() const
 175 {
 176   // file should be opened and we must be in it's beginning
 177   wxASSERT( m_file.IsOpened() && m_file.Tell() == 0 );
 178
 179   // scan the file lines
 180   size_t nUnix = 0,     // number of '\n's alone
 181        nDos  = 0,     // number of '\r\n'
 182        nMac  = 0;     // number of '\r's
 183
 184   // we take MAX_LINES_SCAN in the beginning, middle and the end of file
 185   #define MAX_LINES_SCAN    (10)
 186   size_t nCount = m_aLines.Count() / 3,
 187        nScan =  nCount > 3*MAX_LINES_SCAN ? MAX_LINES_SCAN : nCount / 3;
 188
 189   #define   AnalyseLine(n)              \
 190     switch ( m_aTypes[n] ) {            \
 191       case wxTextFileType_Unix: nUnix++; break;   \
 192       case wxTextFileType_Dos:  nDos++;  break;   \
 193       case wxTextFileType_Mac:  nMac++;  break;   \
 194       default: wxFAIL_MSG(_("unknown line terminator")); \
 195     }
 196
 197   size_t n;
 198   for ( n = 0; n < nScan; n++ )     // the beginning
 199     AnalyseLine(n);
 200   for ( n = (nCount - nScan)/2; n < (nCount + nScan)/2; n++ )
 201     AnalyseLine(n);
 202   for ( n = nCount - nScan; n < nCount; n++ )
 203     AnalyseLine(n);
 204
 205   #undef   AnalyseLine
 206
 207   // interpret the results (FIXME far from being even 50% fool proof)
 208   if ( nDos + nUnix + nMac == 0 ) {
 209     // no newlines at all
 210     wxLogWarning(_("'%s' is probably a binary file."), m_strFile.c_str());
 211   }
 212   else {
 213     #define   GREATER_OF(t1, t2) n##t1 == n##t2 ? typeDefault               \
 214                                                 : n##t1 > n##t2             \
 215                                                     ? wxTextFileType_##t1   \
 216                                                     : wxTextFileType_##t2
 217
 218     // Watcom C++ doesn't seem to be able to handle the macro
 219 #if !defined(__WATCOMC__)
 220     if ( nDos > nUnix )
 221       return GREATER_OF(Dos, Mac);
 222     else if ( nDos < nUnix )
 223       return GREATER_OF(Unix, Mac);
 224     else {
 225       // nDos == nUnix
 226       return nMac > nDos ? wxTextFileType_Mac : typeDefault;
 227     }
 228 #endif // __WATCOMC__
 229
 230     #undef    GREATER_OF
 231   }
 232
 233   return typeDefault;
 234 }
 235
 236 bool wxTextFile::Read()
 237 {
 238   // file should be opened and we must be in it's beginning
 239   wxASSERT( m_file.IsOpened() && m_file.Tell() == 0 );
 240
 241   wxString str;
 242   char ch, chLast = '\0';
 243   char buf[1024];
 244   int n, nRead;
 245   while ( !m_file.Eof() ) {
 246     nRead = m_file.Read(buf, WXSIZEOF(buf));
 247     if ( nRead == wxInvalidOffset ) {
 248       // read error (error message already given in wxFile::Read)
 249       return FALSE;
 250     }
 251
 252     for ( n = 0; n < nRead; n++ ) {
 253       ch = buf[n];
 254       switch ( ch ) {
 255         case '\n':
 256           // Dos/Unix line termination
 257           m_aLines.Add(str);
 258           m_aTypes.Add(chLast == '\r' ? wxTextFileType_Dos
 259                                       : wxTextFileType_Unix);
 260           str.Empty();
 261           chLast = '\n';
 262           break;
 263
 264         case '\r':
 265           if ( chLast == '\r' ) {
 266             // Mac empty line
 267             m_aLines.Add("");
 268             m_aTypes.Add(wxTextFileType_Mac);
 269           }
 270           else
 271             chLast = '\r';
 272           break;
 273
 274         default:
 275           if ( chLast == '\r' ) {
 276             // Mac line termination
 277             m_aLines.Add(str);
 278             m_aTypes.Add(wxTextFileType_Mac);
 279             chLast = ch;
 280             str = ch;
 281           }
 282           else {
 283             // add to the current line
 284             str += ch;
 285           }
 286       }
 287     }
 288   }
 289
 290   // anything in the last line?
 291   if ( !str.IsEmpty() ) {
 292     m_aTypes.Add(wxTextFileType_None);  // no line terminator
 293     m_aLines.Add(str);
 294   }
 295
 296   return TRUE;
 297 }
 298
 299 bool wxTextFile::Close()
 300 {
 301     m_aTypes.Clear();
 302     m_aLines.Clear();
 303     m_nCurLine = 0;
 304     m_isOpened = FALSE;
 305
 306     return TRUE;
 307 }
 308
 309 bool wxTextFile::Write(wxTextFileType typeNew)
 310 {
 311   wxTempFile fileTmp(m_strFile);
 312
 313   if ( !fileTmp.IsOpened() ) {
 314     wxLogError(_("can't write file '%s' to disk."), m_strFile.c_str());
 315     return FALSE;
 316   }
 317
 318   size_t nCount = m_aLines.Count();
 319   for ( size_t n = 0; n < nCount; n++ ) {
 320     fileTmp.Write(m_aLines[n] +
 321                   GetEOL(typeNew == wxTextFileType_None ? m_aTypes[n]
 322                                                         : typeNew));
 323   }
 324
 325   // replace the old file with this one
 326   return fileTmp.Commit();
 327 }
 328
 329 #endif // wxUSE_TEXTFILE
 330