src/common/textfile.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/common/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 licence
  10 ///////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // headers
  14 // ============================================================================
  15
  16 #include  "wx/wxprec.h"
  17
  18 #ifdef    __BORLANDC__
  19     #pragma hdrstop
  20 #endif  //__BORLANDC__
  21
  22 #if !wxUSE_FILE || !wxUSE_TEXTBUFFER
  23     #undef wxUSE_TEXTFILE
  24     #define wxUSE_TEXTFILE 0
  25 #endif // wxUSE_FILE
  26
  27 #if wxUSE_TEXTFILE
  28
  29 #ifndef WX_PRECOMP
  30     #include "wx/string.h"
  31     #include "wx/intl.h"
  32     #include "wx/file.h"
  33     #include "wx/log.h"
  34 #endif
  35
  36 #include "wx/textfile.h"
  37 #include "wx/filename.h"
  38 #include "wx/buffer.h"
  39
  40 // ============================================================================
  41 // wxTextFile class implementation
  42 // ============================================================================
  43
  44 wxTextFile::wxTextFile(const wxString& strFileName)
  45           : wxTextBuffer(strFileName)
  46 {
  47 }
  48
  49
  50 // ----------------------------------------------------------------------------
  51 // file operations
  52 // ----------------------------------------------------------------------------
  53
  54 bool wxTextFile::OnExists() const
  55 {
  56     return wxFile::Exists(m_strBufferName);
  57 }
  58
  59
  60 bool wxTextFile::OnOpen(const wxString &strBufferName, wxTextBufferOpenMode OpenMode)
  61 {
  62     wxFile::OpenMode FileOpenMode;
  63
  64     switch ( OpenMode )
  65     {
  66         default:
  67             wxFAIL_MSG( _T("unknown open mode in wxTextFile::Open") );
  68             // fall through
  69
  70         case ReadAccess :
  71             FileOpenMode = wxFile::read;
  72             break;
  73
  74         case WriteAccess :
  75             FileOpenMode = wxFile::write;
  76             break;
  77     }
  78
  79     return m_file.Open(strBufferName.c_str(), FileOpenMode);
  80 }
  81
  82
  83 bool wxTextFile::OnClose()
  84 {
  85     return m_file.Close();
  86 }
  87
  88
  89 bool wxTextFile::OnRead(wxMBConv& conv)
  90 {
  91     // file should be opened and we must be in it's beginning
  92     wxASSERT( m_file.IsOpened() && m_file.Tell() == 0 );
  93
  94     // read the entire file in memory: this is not the most efficient thing to
  95     // do but there is no good way to avoid it in Unicode build because if we
  96     // read the file block by block we can't convert each block to Unicode
  97     // separately (the last multibyte char in the block might be only partially
  98     // read and so the conversion would fail) and, as the file contents is kept
  99     // in memory by wxTextFile anyhow, it shouldn't be a big problem to read
 100     // the file entirely
 101     const size_t bufSize = (size_t)(m_file.Length() + 4 /* for trailing NULs */ );
 102     size_t bufPos = 0;
 103     wxCharBuffer buf(bufSize - 1 /* it adds 1 internally */);
 104
 105     char block[1024];
 106     for ( bool eof = false; !eof; )
 107     {
 108         // try to read up to the size of the entire block
 109         ssize_t nRead = m_file.Read(block, WXSIZEOF(block));
 110
 111         if ( nRead == wxInvalidOffset )
 112         {
 113             // read error (error message already given in wxFile::Read)
 114             return false;
 115         }
 116
 117         eof = nRead == 0;
 118         if ( eof )
 119         {
 120             // append 4 trailing NUL bytes: this is needed to ensure that the
 121             // string is going to be NUL-terminated, whatever is the encoding
 122             // used (even UTF-32)
 123             block[0] =
 124             block[1] =
 125             block[2] =
 126             block[3] = '\0';
 127             nRead = 4;
 128         }
 129
 130         // this shouldn't happen but don't overwrite the buffer if it does
 131         wxCHECK_MSG( bufPos + nRead <= bufSize, false,
 132                      _T("read more than file length?") );
 133
 134         // append to the buffer
 135         memcpy(buf.data() + bufPos, block, nRead);
 136         bufPos += nRead;
 137     }
 138
 139     const wxString str(buf, conv);
 140
 141     // this doesn't risk to happen in ANSI build
 142 #if wxUSE_UNICODE
 143     if ( bufSize > 4 && str.empty() )
 144     {
 145         wxLogError(_("Failed to convert file contents to Unicode."));
 146         return false;
 147     }
 148 #endif // wxUSE_UNICODE
 149
 150     free(buf.release()); // we don't need this memory any more
 151
 152
 153     // now break the buffer in lines
 154
 155     // last processed character, we need to know if it was a CR or not
 156     wxChar chLast = '\0';
 157
 158     // the beginning of the current line, changes inside the loop
 159     wxString::const_iterator lineStart = str.begin();
 160     const wxString::const_iterator end = str.end();
 161     for ( wxString::const_iterator p = lineStart; p != end; p++ )
 162     {
 163         const wxChar ch = *p;
 164         switch ( ch )
 165         {
 166             case '\n':
 167                 // could be a DOS or Unix EOL
 168                 if ( chLast == '\r' )
 169                 {
 170                     AddLine(wxString(lineStart, p - 1), wxTextFileType_Dos);
 171                 }
 172                 else // bare '\n', Unix style
 173                 {
 174                     AddLine(wxString(lineStart, p), wxTextFileType_Unix);
 175                 }
 176
 177                 lineStart = p + 1;
 178                 break;
 179
 180             case '\r':
 181                 if ( chLast == '\r' )
 182                 {
 183                     // Mac empty line
 184                     AddLine(wxEmptyString, wxTextFileType_Mac);
 185                     lineStart = p + 1;
 186                 }
 187                 //else: we don't know what this is yet -- could be a Mac EOL or
 188                 //      start of DOS EOL so wait for next char
 189                 break;
 190
 191             default:
 192                 if ( chLast == '\r' )
 193                 {
 194                     // Mac line termination
 195                     AddLine(wxString(lineStart, p - 1), wxTextFileType_Mac);
 196                     lineStart = p;
 197                 }
 198         }
 199
 200         chLast = ch;
 201     }
 202
 203     // anything in the last line?
 204     if ( lineStart != end )
 205     {
 206         // add unterminated last line
 207         AddLine(wxString(lineStart, end), wxTextFileType_None);
 208     }
 209
 210     return true;
 211 }
 212
 213
 214 bool wxTextFile::OnWrite(wxTextFileType typeNew, wxMBConv& conv)
 215 {
 216     wxFileName fn = m_strBufferName;
 217
 218     // We do NOT want wxPATH_NORM_CASE here, or the case will not
 219     // be preserved.
 220     if ( !fn.IsAbsolute() )
 221         fn.Normalize(wxPATH_NORM_ENV_VARS | wxPATH_NORM_DOTS | wxPATH_NORM_TILDE |
 222                      wxPATH_NORM_ABSOLUTE | wxPATH_NORM_LONG);
 223
 224     wxTempFile fileTmp(fn.GetFullPath());
 225
 226     if ( !fileTmp.IsOpened() ) {
 227         wxLogError(_("can't write buffer '%s' to disk."), m_strBufferName.c_str());
 228         return false;
 229     }
 230
 231     size_t nCount = GetLineCount();
 232     for ( size_t n = 0; n < nCount; n++ ) {
 233         fileTmp.Write(GetLine(n) +
 234                       GetEOL(typeNew == wxTextFileType_None ? GetLineType(n)
 235                                                             : typeNew),
 236                       conv);
 237     }
 238
 239     // replace the old file with this one
 240     return fileTmp.Commit();
 241 }
 242
 243 #endif // wxUSE_TEXTFILE