src/common/ffile.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        ffile.cpp
   3 // Purpose:     wxFFile encapsulates "FILE *" IO stream
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     14.07.99
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 1998 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 // ----------------------------------------------------------------------------
  17 // headers
  18 // ----------------------------------------------------------------------------
  19
  20 #if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
  21     #pragma implementation "ffile.h"
  22 #endif
  23
  24 // For compilers that support precompilation, includes "wx.h".
  25 #include "wx/wxprec.h"
  26
  27 #ifdef __BORLANDC__
  28   #pragma hdrstop
  29 #endif
  30
  31 #if wxUSE_FFILE
  32
  33 #ifndef WX_PRECOMP
  34     #include "wx/intl.h"
  35     #include "wx/log.h"
  36 #endif
  37
  38 #include "wx/ffile.h"
  39
  40 // ============================================================================
  41 // implementation
  42 // ============================================================================
  43
  44 // ----------------------------------------------------------------------------
  45 // seek and tell with large file support if available
  46 // ----------------------------------------------------------------------------
  47
  48 #ifdef HAVE_FSEEKO
  49 #   define wxFseek fseeko
  50 #   define wxFtell ftello
  51 #else
  52 #   define wxFseek fseek
  53 #   define wxFtell ftell
  54 #endif
  55
  56 // ----------------------------------------------------------------------------
  57 // opening the file
  58 // ----------------------------------------------------------------------------
  59
  60 wxFFile::wxFFile(const wxChar *filename, const wxChar *mode)
  61 {
  62     Detach();
  63
  64     (void)Open(filename, mode);
  65 }
  66
  67 bool wxFFile::Open(const wxChar *filename, const wxChar *mode)
  68 {
  69     wxASSERT_MSG( !m_fp, wxT("should close or detach the old file first") );
  70
  71     m_fp = wxFopen(filename, mode);
  72
  73     if ( !m_fp )
  74     {
  75         wxLogSysError(_("can't open file '%s'"), filename);
  76
  77         return false;
  78     }
  79
  80     m_name = filename;
  81
  82     return true;
  83 }
  84
  85 bool wxFFile::Close()
  86 {
  87     if ( IsOpened() )
  88     {
  89         if ( fclose(m_fp) != 0 )
  90         {
  91             wxLogSysError(_("can't close file '%s'"), m_name.c_str());
  92
  93             return false;
  94         }
  95
  96         Detach();
  97     }
  98
  99     return true;
 100 }
 101
 102 // ----------------------------------------------------------------------------
 103 // read/write
 104 // ----------------------------------------------------------------------------
 105
 106 bool wxFFile::ReadAll(wxString *str, wxMBConv& conv)
 107 {
 108     wxCHECK_MSG( str, false, wxT("invalid parameter") );
 109     wxCHECK_MSG( IsOpened(), false, wxT("can't read from closed file") );
 110     wxCHECK_MSG( Length() >= 0, false, wxT("invalid length") );
 111     size_t length = (size_t)Length();
 112     wxCHECK_MSG( (wxFileOffset)length == Length(), false, wxT("huge file not supported") );
 113
 114     clearerr(m_fp);
 115
 116     const size_t fileLen = Length();
 117     wxCharBuffer buf(fileLen + 1);
 118
 119     // note that realLen may be less than fileLen for text files with DOS EOLs
 120     // ('\r's get dropped by CRT when reading which means that we have
 121     // realLen = fileLen - numOfLinesInTheFile)
 122     size_t realLen = fread(buf.data(), sizeof(char), fileLen, m_fp);
 123
 124     if ( Error() )
 125     {
 126         wxLogSysError(_("Read error on file '%s'"), m_name.c_str());
 127
 128         return false;
 129     }
 130
 131     buf.data()[realLen] = 0;
 132     *str = wxString(buf, conv);
 133
 134     return true;
 135 }
 136
 137 size_t wxFFile::Read(void *pBuf, size_t nCount)
 138 {
 139     wxCHECK_MSG( pBuf, FALSE, wxT("invalid parameter") );
 140     wxCHECK_MSG( IsOpened(), FALSE, wxT("can't read from closed file") );
 141
 142     size_t nRead = fread(pBuf, 1, nCount, m_fp);
 143     if ( (nRead < nCount) && Error() )
 144     {
 145         wxLogSysError(_("Read error on file '%s'"), m_name.c_str());
 146     }
 147
 148     return nRead;
 149 }
 150
 151 size_t wxFFile::Write(const void *pBuf, size_t nCount)
 152 {
 153     wxCHECK_MSG( pBuf, FALSE, wxT("invalid parameter") );
 154     wxCHECK_MSG( IsOpened(), FALSE, wxT("can't write to closed file") );
 155
 156     size_t nWritten = fwrite(pBuf, 1, nCount, m_fp);
 157     if ( nWritten < nCount )
 158     {
 159         wxLogSysError(_("Write error on file '%s'"), m_name.c_str());
 160     }
 161
 162     return nWritten;
 163 }
 164
 165 bool wxFFile::Flush()
 166 {
 167     if ( IsOpened() )
 168     {
 169         // fflush returns non-zero on error
 170         //
 171         if ( fflush(m_fp) )
 172         {
 173             wxLogSysError(_("failed to flush the file '%s'"), m_name.c_str());
 174
 175             return false;
 176         }
 177     }
 178
 179     return true;
 180 }
 181
 182 // ----------------------------------------------------------------------------
 183 // seeking
 184 // ----------------------------------------------------------------------------
 185
 186 bool wxFFile::Seek(wxFileOffset ofs, wxSeekMode mode)
 187 {
 188     wxCHECK_MSG( IsOpened(), false, wxT("can't seek on closed file") );
 189
 190     int origin;
 191     switch ( mode )
 192     {
 193         default:
 194             wxFAIL_MSG(wxT("unknown seek mode"));
 195             // still fall through
 196
 197         case wxFromStart:
 198             origin = SEEK_SET;
 199             break;
 200
 201         case wxFromCurrent:
 202             origin = SEEK_CUR;
 203             break;
 204
 205         case wxFromEnd:
 206             origin = SEEK_END;
 207             break;
 208     }
 209
 210 #ifndef HAVE_FSEEKO
 211     if ((long)ofs != ofs)
 212     {
 213         wxLogError(_("Seek error on file '%s' (large files not supported by stdio)"), m_name.c_str());
 214
 215         return false;
 216     }
 217
 218     if ( wxFseek(m_fp, (long)ofs, origin) != 0 )
 219 #else
 220     if ( wxFseek(m_fp, ofs, origin) != 0 )
 221 #endif
 222     {
 223         wxLogSysError(_("Seek error on file '%s'"), m_name.c_str());
 224
 225         return false;
 226     }
 227
 228     return true;
 229 }
 230
 231 wxFileOffset wxFFile::Tell() const
 232 {
 233     wxCHECK_MSG( IsOpened(), wxInvalidOffset,
 234                  _T("wxFFile::Tell(): file is closed!") );
 235
 236     wxFileOffset rc = wxFtell(m_fp);
 237     if ( rc == wxInvalidOffset )
 238     {
 239         wxLogSysError(_("Can't find current position in file '%s'"),
 240                       m_name.c_str());
 241     }
 242
 243     return rc;
 244 }
 245
 246 wxFileOffset wxFFile::Length() const
 247 {
 248     wxCHECK_MSG( IsOpened(), wxInvalidOffset,
 249                  _T("wxFFile::Length(): file is closed!") );
 250
 251     wxFFile& self = *(wxFFile *)this;   // const_cast
 252
 253     wxFileOffset posOld = Tell();
 254     if ( posOld != wxInvalidOffset )
 255     {
 256         if ( self.SeekEnd() )
 257         {
 258             wxFileOffset len = Tell();
 259
 260             (void)self.Seek(posOld);
 261
 262             return len;
 263         }
 264     }
 265
 266     return wxInvalidOffset;
 267 }
 268
 269 #endif // wxUSE_FFILE