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     wxString eol = GetEOL(type), result;
  84
  85     // optimization: we know that the length of the new string will be about
  86     // the same as the length of the old one, so prealloc memory to aviod
  87     // unnecessary relocations
  88     result.Alloc(text.Len());
  89
  90     wxChar chLast = 0;
  91     for ( const wxChar *pc = text.c_str(); *pc; pc++ )
  92     {
  93         wxChar ch = *pc;
  94         switch ( ch ) {
  95             case _T('\n'):
  96                 // Dos/Unix line termination
  97                 result += eol;
  98                 chLast = 0;
  99                 break;
 100
 101             case _T('\r'):
 102                 if ( chLast == _T('\r') ) {
 103                     // Mac empty line
 104                     result += eol;
 105                 }
 106                 else {
 107                     // just remember it: we don't know whether it is just "\r"
 108                     // or "\r\n" yet
 109                     chLast = _T('\r');
 110                 }
 111                 break;
 112
 113             default:
 114                 if ( chLast == _T('\r') ) {
 115                     // Mac line termination
 116                     result += eol;
 117                 }
 118
 119                 // add to the current line
 120                 result += ch;
 121         }
 122     }
 123
 124     if ( chLast ) {
 125         // trailing '\r'
 126         result += eol;
 127     }
 128
 129     return result;
 130 }
 131
 132 #if wxUSE_TEXTFILE
 133
 134 // ----------------------------------------------------------------------------
 135 // ctors & dtor
 136 // ----------------------------------------------------------------------------
 137
 138 wxTextFile::wxTextFile(const wxString& strFile) : m_strFile(strFile)
 139 {
 140   m_nCurLine = 0;
 141   m_isOpened = FALSE;
 142 }
 143
 144 wxTextFile::~wxTextFile()
 145 {
 146   // m_file dtor called automatically
 147 }
 148
 149 // ----------------------------------------------------------------------------
 150 // file operations
 151 // ----------------------------------------------------------------------------
 152
 153 bool wxTextFile::Exists() const
 154 {
 155     return wxFile::Exists(m_strFile);
 156 }
 157
 158 bool wxTextFile::Open(const wxString& strFile)
 159 {
 160   m_strFile = strFile;
 161
 162   return Open();
 163 }
 164
 165 bool wxTextFile::Open()
 166 {
 167   // file name must be either given in ctor or in Open(const wxString&)
 168   wxASSERT( !m_strFile.IsEmpty() );
 169
 170   // open file in read-only mode
 171   if ( !m_file.Open(m_strFile) )
 172     return FALSE;
 173
 174   // read file into memory
 175   m_isOpened = Read();
 176
 177   m_file.Close();
 178
 179   return m_isOpened;
 180 }
 181
 182 // analyse some lines of the file trying to guess it's type.
 183 // if it fails, it assumes the native type for our platform.
 184 wxTextFileType wxTextFile::GuessType() const
 185 {
 186   // file should be opened and we must be in it's beginning
 187   wxASSERT( m_file.IsOpened() && m_file.Tell() == 0 );
 188
 189   // scan the file lines
 190   size_t nUnix = 0,     // number of '\n's alone
 191        nDos  = 0,     // number of '\r\n'
 192        nMac  = 0;     // number of '\r's
 193
 194   // we take MAX_LINES_SCAN in the beginning, middle and the end of file
 195   #define MAX_LINES_SCAN    (10)
 196   size_t nCount = m_aLines.Count() / 3,
 197        nScan =  nCount > 3*MAX_LINES_SCAN ? MAX_LINES_SCAN : nCount / 3;
 198
 199   #define   AnalyseLine(n)              \
 200     switch ( m_aTypes[n] ) {            \
 201       case wxTextFileType_Unix: nUnix++; break;   \
 202       case wxTextFileType_Dos:  nDos++;  break;   \
 203       case wxTextFileType_Mac:  nMac++;  break;   \
 204       default: wxFAIL_MSG(_("unknown line terminator")); \
 205     }
 206
 207   size_t n;
 208   for ( n = 0; n < nScan; n++ )     // the beginning
 209     AnalyseLine(n);
 210   for ( n = (nCount - nScan)/2; n < (nCount + nScan)/2; n++ )
 211     AnalyseLine(n);
 212   for ( n = nCount - nScan; n < nCount; n++ )
 213     AnalyseLine(n);
 214
 215   #undef   AnalyseLine
 216
 217   // interpret the results (FIXME far from being even 50% fool proof)
 218   if ( nDos + nUnix + nMac == 0 ) {
 219     // no newlines at all
 220     wxLogWarning(_("'%s' is probably a binary file."), m_strFile.c_str());
 221   }
 222   else {
 223     #define   GREATER_OF(t1, t2) n##t1 == n##t2 ? typeDefault               \
 224                                                 : n##t1 > n##t2             \
 225                                                     ? wxTextFileType_##t1   \
 226                                                     : wxTextFileType_##t2
 227
 228     // Watcom C++ doesn't seem to be able to handle the macro
 229 #if !defined(__WATCOMC__)
 230     if ( nDos > nUnix )
 231       return GREATER_OF(Dos, Mac);
 232     else if ( nDos < nUnix )
 233       return GREATER_OF(Unix, Mac);
 234     else {
 235       // nDos == nUnix
 236       return nMac > nDos ? wxTextFileType_Mac : typeDefault;
 237     }
 238 #endif // __WATCOMC__
 239
 240     #undef    GREATER_OF
 241   }
 242
 243   return typeDefault;
 244 }
 245
 246 bool wxTextFile::Read()
 247 {
 248   // file should be opened and we must be in it's beginning
 249   wxASSERT( m_file.IsOpened() && m_file.Tell() == 0 );
 250
 251   wxString str;
 252   char ch, chLast = '\0';
 253   char buf[1024];
 254   int n, nRead;
 255   while ( !m_file.Eof() ) {
 256     nRead = m_file.Read(buf, WXSIZEOF(buf));
 257     if ( nRead == wxInvalidOffset ) {
 258       // read error (error message already given in wxFile::Read)
 259       return FALSE;
 260     }
 261
 262     for ( n = 0; n < nRead; n++ ) {
 263       ch = buf[n];
 264       switch ( ch ) {
 265         case '\n':
 266           // Dos/Unix line termination
 267           m_aLines.Add(str);
 268           m_aTypes.Add(chLast == '\r' ? wxTextFileType_Dos
 269                                       : wxTextFileType_Unix);
 270           str.Empty();
 271           chLast = '\n';
 272           break;
 273
 274         case '\r':
 275           if ( chLast == '\r' ) {
 276             // Mac empty line
 277             m_aLines.Add(wxEmptyString);
 278             m_aTypes.Add(wxTextFileType_Mac);
 279           }
 280           else
 281             chLast = '\r';
 282           break;
 283
 284         default:
 285           if ( chLast == '\r' ) {
 286             // Mac line termination
 287             m_aLines.Add(str);
 288             m_aTypes.Add(wxTextFileType_Mac);
 289             chLast = ch;
 290             str = ch;
 291           }
 292           else {
 293             // add to the current line
 294             str += ch;
 295           }
 296       }
 297     }
 298   }
 299
 300   // anything in the last line?
 301   if ( !str.IsEmpty() ) {
 302     m_aTypes.Add(wxTextFileType_None);  // no line terminator
 303     m_aLines.Add(str);
 304   }
 305
 306   return TRUE;
 307 }
 308
 309 bool wxTextFile::Close()
 310 {
 311     m_aTypes.Clear();
 312     m_aLines.Clear();
 313     m_nCurLine = 0;
 314     m_isOpened = FALSE;
 315
 316     return TRUE;
 317 }
 318
 319 bool wxTextFile::Write(wxTextFileType typeNew)
 320 {
 321   wxTempFile fileTmp(m_strFile);
 322
 323   if ( !fileTmp.IsOpened() ) {
 324     wxLogError(_("can't write file '%s' to disk."), m_strFile.c_str());
 325     return FALSE;
 326   }
 327
 328   size_t nCount = m_aLines.Count();
 329   for ( size_t n = 0; n < nCount; n++ ) {
 330     fileTmp.Write(m_aLines[n] +
 331                   GetEOL(typeNew == wxTextFileType_None ? m_aTypes[n]
 332                                                         : typeNew));
 333   }
 334
 335   // replace the old file with this one
 336   return fileTmp.Commit();
 337 }
 338
 339 #endif // wxUSE_TEXTFILE
 340