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(_T(""));
  71       case wxTextFileType_Unix: return wxT(_T("\n"));
  72       case wxTextFileType_Dos:  return wxT(_T("\r\n"));
  73       case wxTextFileType_Mac:  return wxT(_T("\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
 123                 // add to the current line
 124                 result += ch;
 125         }
 126     }
 127
 128     if ( chLast ) {
 129         // trailing '\r'
 130         result += eol;
 131     }
 132
 133     return result;
 134 }
 135
 136 #if wxUSE_TEXTFILE
 137
 138 // ----------------------------------------------------------------------------
 139 // ctors & dtor
 140 // ----------------------------------------------------------------------------
 141
 142 wxTextFile::wxTextFile(const wxString& strFile) : m_strFile(strFile)
 143 {
 144   m_nCurLine = 0;
 145   m_isOpened = FALSE;
 146 }
 147
 148 wxTextFile::~wxTextFile()
 149 {
 150   // m_file dtor called automatically
 151 }
 152
 153 // ----------------------------------------------------------------------------
 154 // file operations
 155 // ----------------------------------------------------------------------------
 156
 157 bool wxTextFile::Exists() const
 158 {
 159     return wxFile::Exists(m_strFile);
 160 }
 161
 162 bool wxTextFile::Open(const wxString& strFile)
 163 {
 164   m_strFile = strFile;
 165
 166   return Open();
 167 }
 168
 169 bool wxTextFile::Open()
 170 {
 171   // file name must be either given in ctor or in Open(const wxString&)
 172   wxASSERT( !m_strFile.IsEmpty() );
 173
 174   // open file in read-only mode
 175   if ( !m_file.Open(m_strFile) )
 176     return FALSE;
 177
 178   // read file into memory
 179   m_isOpened = Read();
 180
 181   m_file.Close();
 182
 183   return m_isOpened;
 184 }
 185
 186 // analyse some lines of the file trying to guess it's type.
 187 // if it fails, it assumes the native type for our platform.
 188 wxTextFileType wxTextFile::GuessType() const
 189 {
 190   // file should be opened and we must be in it's beginning
 191   wxASSERT( m_file.IsOpened() && m_file.Tell() == 0 );
 192
 193   // scan the file lines
 194   size_t nUnix = 0,     // number of '\n's alone
 195        nDos  = 0,     // number of '\r\n'
 196        nMac  = 0;     // number of '\r's
 197
 198   // we take MAX_LINES_SCAN in the beginning, middle and the end of file
 199   #define MAX_LINES_SCAN    (10)
 200   size_t nCount = m_aLines.Count() / 3,
 201        nScan =  nCount > 3*MAX_LINES_SCAN ? MAX_LINES_SCAN : nCount / 3;
 202
 203   #define   AnalyseLine(n)              \
 204     switch ( m_aTypes[n] ) {            \
 205       case wxTextFileType_Unix: nUnix++; break;   \
 206       case wxTextFileType_Dos:  nDos++;  break;   \
 207       case wxTextFileType_Mac:  nMac++;  break;   \
 208       default: wxFAIL_MSG(_("unknown line terminator")); \
 209     }
 210
 211   size_t n;
 212   for ( n = 0; n < nScan; n++ )     // the beginning
 213     AnalyseLine(n);
 214   for ( n = (nCount - nScan)/2; n < (nCount + nScan)/2; n++ )
 215     AnalyseLine(n);
 216   for ( n = nCount - nScan; n < nCount; n++ )
 217     AnalyseLine(n);
 218
 219   #undef   AnalyseLine
 220
 221   // interpret the results (FIXME far from being even 50% fool proof)
 222   if ( nDos + nUnix + nMac == 0 ) {
 223     // no newlines at all
 224     wxLogWarning(_("'%s' is probably a binary file."), m_strFile.c_str());
 225   }
 226   else {
 227     #define   GREATER_OF(t1, t2) n##t1 == n##t2 ? typeDefault               \
 228                                                 : n##t1 > n##t2             \
 229                                                     ? wxTextFileType_##t1   \
 230                                                     : wxTextFileType_##t2
 231
 232     // Watcom C++ doesn't seem to be able to handle the macro
 233 #if !defined(__WATCOMC__)
 234     if ( nDos > nUnix )
 235       return GREATER_OF(Dos, Mac);
 236     else if ( nDos < nUnix )
 237       return GREATER_OF(Unix, Mac);
 238     else {
 239       // nDos == nUnix
 240       return nMac > nDos ? wxTextFileType_Mac : typeDefault;
 241     }
 242 #endif // __WATCOMC__
 243
 244     #undef    GREATER_OF
 245   }
 246
 247   return typeDefault;
 248 }
 249
 250 bool wxTextFile::Read()
 251 {
 252   // file should be opened and we must be in it's beginning
 253   wxASSERT( m_file.IsOpened() && m_file.Tell() == 0 );
 254
 255   wxString str;
 256   char ch, chLast = '\0';
 257   char buf[1024];
 258   int n, nRead;
 259   while ( !m_file.Eof() ) {
 260     nRead = m_file.Read(buf, WXSIZEOF(buf));
 261     if ( nRead == wxInvalidOffset ) {
 262       // read error (error message already given in wxFile::Read)
 263       return FALSE;
 264     }
 265
 266     for ( n = 0; n < nRead; n++ ) {
 267       ch = buf[n];
 268       switch ( ch ) {
 269         case '\n':
 270           // Dos/Unix line termination
 271           m_aLines.Add(str);
 272           m_aTypes.Add(chLast == '\r' ? wxTextFileType_Dos
 273                                       : wxTextFileType_Unix);
 274           str.Empty();
 275           chLast = '\n';
 276           break;
 277
 278         case '\r':
 279           if ( chLast == '\r' ) {
 280             // Mac empty line
 281             m_aLines.Add(wxEmptyString);
 282             m_aTypes.Add(wxTextFileType_Mac);
 283           }
 284           else
 285             chLast = '\r';
 286           break;
 287
 288         default:
 289           if ( chLast == '\r' ) {
 290             // Mac line termination
 291             m_aLines.Add(str);
 292             m_aTypes.Add(wxTextFileType_Mac);
 293             chLast = ch;
 294             str = ch;
 295           }
 296           else {
 297             // add to the current line
 298             str += ch;
 299           }
 300       }
 301     }
 302   }
 303
 304   // anything in the last line?
 305   if ( !str.IsEmpty() ) {
 306     m_aTypes.Add(wxTextFileType_None);  // no line terminator
 307     m_aLines.Add(str);
 308   }
 309
 310   return TRUE;
 311 }
 312
 313 bool wxTextFile::Close()
 314 {
 315     m_aTypes.Clear();
 316     m_aLines.Clear();
 317     m_nCurLine = 0;
 318     m_isOpened = FALSE;
 319
 320     return TRUE;
 321 }
 322
 323 bool wxTextFile::Write(wxTextFileType typeNew)
 324 {
 325   wxTempFile fileTmp(m_strFile);
 326
 327   if ( !fileTmp.IsOpened() ) {
 328     wxLogError(_("can't write file '%s' to disk."), m_strFile.c_str());
 329     return FALSE;
 330   }
 331
 332   size_t nCount = m_aLines.Count();
 333   for ( size_t n = 0; n < nCount; n++ ) {
 334     fileTmp.Write(m_aLines[n] +
 335                   GetEOL(typeNew == wxTextFileType_None ? m_aTypes[n]
 336                                                         : typeNew));
 337   }
 338
 339   // replace the old file with this one
 340   return fileTmp.Commit();
 341 }
 342
 343 #endif // wxUSE_TEXTFILE
 344