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