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(wxT("bad file type in wxTextFile::GetEOL."));
  68         // fall through nevertheless - we must return something...
  69
  70       case wxTextFileType_None: return wxT("");
  71       case wxTextFileType_Unix: return wxT("\n");
  72       case wxTextFileType_Dos:  return wxT("\r\n");
  73       case wxTextFileType_Mac:  return wxT("\r");
  74     }
  75 }
  76
  77 wxString wxTextFile::Translate(const wxString& text, wxTextFileType type)
  78 {
  79     // don't do anything if there is nothing to do
  80     if ( type == wxTextFileType_None )
  81         return text;
  82
  83     // GRG: don't do anything either if it is empty
  84     if ( text.IsEmpty() )
  85         return text;
  86
  87     wxString eol = GetEOL(type), result;
  88
  89     // optimization: we know that the length of the new string will be about
  90     // the same as the length of the old one, so prealloc memory to aviod
  91     // unnecessary relocations
  92     result.Alloc(text.Len());
  93
  94     wxChar chLast = 0;
  95     for ( const wxChar *pc = text.c_str(); *pc; pc++ )
  96     {
  97         wxChar ch = *pc;
  98         switch ( ch ) {
  99             case _T('\n'):
 100                 // Dos/Unix line termination
 101                 result += eol;
 102                 chLast = 0;
 103                 break;
 104
 105             case _T('\r'):
 106                 if ( chLast == _T('\r') ) {
 107                     // Mac empty line
 108                     result += eol;
 109                 }
 110                 else {
 111                     // just remember it: we don't know whether it is just "\r"
 112                     // or "\r\n" yet
 113                     chLast = _T('\r');
 114                 }
 115                 break;
 116
 117             default:
 118                 if ( chLast == _T('\r') ) {
 119                     // Mac line termination
 120                     result += eol;
 121
 122                     // reset chLast to avoid inserting another eol before the
 123                     // next character
 124                     chLast = 0;
 125                 }
 126
 127                 // add to the current line
 128                 result += ch;
 129         }
 130     }
 131
 132     if ( chLast ) {
 133         // trailing '\r'
 134         result += eol;
 135     }
 136
 137     return result;
 138 }
 139
 140 #if wxUSE_TEXTFILE
 141
 142 // ----------------------------------------------------------------------------
 143 // ctors & dtor
 144 // ----------------------------------------------------------------------------
 145
 146 wxTextFile::wxTextFile(const wxString& strFile) : m_strFile(strFile)
 147 {
 148   m_nCurLine = 0;
 149   m_isOpened = FALSE;
 150 }
 151
 152 wxTextFile::~wxTextFile()
 153 {
 154   // m_file dtor called automatically
 155 }
 156
 157 // ----------------------------------------------------------------------------
 158 // file operations
 159 // ----------------------------------------------------------------------------
 160
 161 bool wxTextFile::Exists() const
 162 {
 163     return wxFile::Exists(m_strFile);
 164 }
 165
 166 bool wxTextFile::Create(const wxString& strFile)
 167 {
 168   m_strFile = strFile;
 169
 170   return Create();
 171 }
 172
 173 bool wxTextFile::Create()
 174 {
 175   // file name must be either given in ctor or in Create(const wxString&)
 176   wxASSERT( !m_strFile.IsEmpty() );
 177
 178   // if the file already exists do nothing
 179   if ( Exists() ) return FALSE;
 180
 181   if ( m_file.Open(m_strFile, wxFile::write) )
 182   {
 183     m_file.Close();
 184     return TRUE;
 185   }
 186   else
 187   {
 188     return FALSE;
 189   }
 190 }
 191
 192 bool wxTextFile::Open(const wxString& strFile)
 193 {
 194   m_strFile = strFile;
 195
 196   return Open();
 197 }
 198
 199 bool wxTextFile::Open()
 200 {
 201   // file name must be either given in ctor or in Open(const wxString&)
 202   wxASSERT( !m_strFile.IsEmpty() );
 203
 204   // open file in read-only mode
 205   if ( !m_file.Open(m_strFile) )
 206     return FALSE;
 207
 208   // read file into memory
 209   m_isOpened = Read();
 210
 211   m_file.Close();
 212
 213   return m_isOpened;
 214 }
 215
 216 // analyse some lines of the file trying to guess it's type.
 217 // if it fails, it assumes the native type for our platform.
 218 wxTextFileType wxTextFile::GuessType() const
 219 {
 220   // file should be opened and we must be in it's beginning
 221   wxASSERT( m_file.IsOpened() && m_file.Tell() == 0 );
 222
 223   // scan the file lines
 224   size_t nUnix = 0,     // number of '\n's alone
 225        nDos  = 0,     // number of '\r\n'
 226        nMac  = 0;     // number of '\r's
 227
 228   // we take MAX_LINES_SCAN in the beginning, middle and the end of file
 229   #define MAX_LINES_SCAN    (10)
 230   size_t nCount = m_aLines.Count() / 3,
 231        nScan =  nCount > 3*MAX_LINES_SCAN ? MAX_LINES_SCAN : nCount / 3;
 232
 233   #define   AnalyseLine(n)              \
 234     switch ( m_aTypes[n] ) {            \
 235       case wxTextFileType_Unix: nUnix++; break;   \
 236       case wxTextFileType_Dos:  nDos++;  break;   \
 237       case wxTextFileType_Mac:  nMac++;  break;   \
 238       default: wxFAIL_MSG(_("unknown line terminator")); \
 239     }
 240
 241   size_t n;
 242   for ( n = 0; n < nScan; n++ )     // the beginning
 243     AnalyseLine(n);
 244   for ( n = (nCount - nScan)/2; n < (nCount + nScan)/2; n++ )
 245     AnalyseLine(n);
 246   for ( n = nCount - nScan; n < nCount; n++ )
 247     AnalyseLine(n);
 248
 249   #undef   AnalyseLine
 250
 251   // interpret the results (FIXME far from being even 50% fool proof)
 252   if ( nDos + nUnix + nMac == 0 ) {
 253     // no newlines at all
 254     wxLogWarning(_("'%s' is probably a binary file."), m_strFile.c_str());
 255   }
 256   else {
 257     #define   GREATER_OF(t1, t2) n##t1 == n##t2 ? typeDefault               \
 258                                                 : n##t1 > n##t2             \
 259                                                     ? wxTextFileType_##t1   \
 260                                                     : wxTextFileType_##t2
 261
 262     // Watcom C++ doesn't seem to be able to handle the macro
 263 #if !defined(__WATCOMC__)
 264     if ( nDos > nUnix )
 265       return GREATER_OF(Dos, Mac);
 266     else if ( nDos < nUnix )
 267       return GREATER_OF(Unix, Mac);
 268     else {
 269       // nDos == nUnix
 270       return nMac > nDos ? wxTextFileType_Mac : typeDefault;
 271     }
 272 #endif // __WATCOMC__
 273
 274     #undef    GREATER_OF
 275   }
 276
 277   return typeDefault;
 278 }
 279
 280 bool wxTextFile::Read()
 281 {
 282   // file should be opened and we must be in it's beginning
 283   wxASSERT( m_file.IsOpened() && m_file.Tell() == 0 );
 284
 285   wxString str;
 286   char ch, chLast = '\0';
 287   char buf[1024];
 288   int n, nRead;
 289   do {
 290     nRead = m_file.Read(buf, WXSIZEOF(buf));
 291     if ( nRead == wxInvalidOffset ) {
 292       // read error (error message already given in wxFile::Read)
 293       return FALSE;
 294     }
 295
 296     for ( n = 0; n < nRead; n++ ) {
 297       ch = buf[n];
 298       switch ( ch ) {
 299         case '\n':
 300           // Dos/Unix line termination
 301           m_aLines.Add(str);
 302           m_aTypes.Add(chLast == '\r' ? wxTextFileType_Dos
 303                                       : wxTextFileType_Unix);
 304           str.Empty();
 305           chLast = '\n';
 306           break;
 307
 308         case '\r':
 309           if ( chLast == '\r' ) {
 310             // Mac empty line
 311             m_aLines.Add(wxEmptyString);
 312             m_aTypes.Add(wxTextFileType_Mac);
 313           }
 314           else
 315             chLast = '\r';
 316           break;
 317
 318         default:
 319           if ( chLast == '\r' ) {
 320             // Mac line termination
 321             m_aLines.Add(str);
 322             m_aTypes.Add(wxTextFileType_Mac);
 323             chLast = ch;
 324             str = ch;
 325           }
 326           else {
 327             // add to the current line
 328             str += ch;
 329           }
 330       }
 331     }
 332   } while ( nRead == WXSIZEOF(buf) );
 333
 334   // anything in the last line?
 335   if ( !str.IsEmpty() ) {
 336     m_aTypes.Add(wxTextFileType_None);  // no line terminator
 337     m_aLines.Add(str);
 338   }
 339
 340   return TRUE;
 341 }
 342
 343 bool wxTextFile::Close()
 344 {
 345     m_aTypes.Clear();
 346     m_aLines.Clear();
 347     m_nCurLine = 0;
 348     m_isOpened = FALSE;
 349
 350     return TRUE;
 351 }
 352
 353 bool wxTextFile::Write(wxTextFileType typeNew)
 354 {
 355   wxTempFile fileTmp(m_strFile);
 356
 357   if ( !fileTmp.IsOpened() ) {
 358     wxLogError(_("can't write file '%s' to disk."), m_strFile.c_str());
 359     return FALSE;
 360   }
 361
 362   size_t nCount = m_aLines.Count();
 363   for ( size_t n = 0; n < nCount; n++ ) {
 364     fileTmp.Write(m_aLines[n] +
 365                   GetEOL(typeNew == wxTextFileType_None ? m_aTypes[n]
 366                                                         : typeNew));
 367   }
 368
 369   // replace the old file with this one
 370   return fileTmp.Commit();
 371 }
 372
 373 #endif // wxUSE_TEXTFILE
 374