src/common/ffile.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/common/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 // For compilers that support precompilation, includes "wx.h".
  21 #include "wx/wxprec.h"
  22
  23 #ifdef __BORLANDC__
  24   #pragma hdrstop
  25 #endif
  26
  27 #if wxUSE_FFILE
  28
  29 #ifndef WX_PRECOMP
  30     #include "wx/intl.h"
  31     #include "wx/log.h"
  32     #include "wx/crt.h"
  33 #endif
  34
  35 #ifdef __WINDOWS__
  36 #include "wx/msw/mslu.h"
  37 #endif
  38
  39 #include "wx/ffile.h"
  40
  41 // ============================================================================
  42 // implementation
  43 // ============================================================================
  44
  45 // ----------------------------------------------------------------------------
  46 // opening the file
  47 // ----------------------------------------------------------------------------
  48
  49 wxFFile::wxFFile(const wxString& filename, const wxString& mode)
  50 {
  51     Detach();
  52
  53     (void)Open(filename, mode);
  54 }
  55
  56 bool wxFFile::Open(const wxString& filename, const wxString& mode)
  57 {
  58     wxASSERT_MSG( !m_fp, wxT("should close or detach the old file first") );
  59
  60     m_fp = wxFopen(filename, mode);
  61
  62     if ( !m_fp )
  63     {
  64         wxLogSysError(_("can't open file '%s'"), filename);
  65
  66         return false;
  67     }
  68
  69     m_name = filename;
  70
  71     return true;
  72 }
  73
  74 bool wxFFile::Close()
  75 {
  76     if ( IsOpened() )
  77     {
  78         if ( fclose(m_fp) != 0 )
  79         {
  80             wxLogSysError(_("can't close file '%s'"), m_name.c_str());
  81
  82             return false;
  83         }
  84
  85         Detach();
  86     }
  87
  88     return true;
  89 }
  90
  91 // ----------------------------------------------------------------------------
  92 // read/write
  93 // ----------------------------------------------------------------------------
  94
  95 bool wxFFile::ReadAll(wxString *str, const wxMBConv& conv)
  96 {
  97     wxCHECK_MSG( str, false, wxT("invalid parameter") );
  98     wxCHECK_MSG( IsOpened(), false, wxT("can't read from closed file") );
  99     wxCHECK_MSG( Length() >= 0, false, wxT("invalid length") );
 100     size_t length = wx_truncate_cast(size_t, Length());
 101     wxCHECK_MSG( (wxFileOffset)length == Length(), false, wxT("huge file not supported") );
 102
 103     clearerr(m_fp);
 104
 105     wxCharBuffer buf(length);
 106
 107     // note that real length may be less than file length for text files with DOS EOLs
 108     // ('\r's get dropped by CRT when reading which means that we have
 109     // realLen = fileLen - numOfLinesInTheFile)
 110     length = fread(buf.data(), 1, length, m_fp);
 111
 112     if ( Error() )
 113     {
 114         wxLogSysError(_("Read error on file '%s'"), m_name.c_str());
 115
 116         return false;
 117     }
 118
 119     buf.data()[length] = 0;
 120
 121     wxString strTmp(buf, conv);
 122     str->swap(strTmp);
 123
 124     return true;
 125 }
 126
 127 size_t wxFFile::Read(void *pBuf, size_t nCount)
 128 {
 129     wxCHECK_MSG( pBuf, 0, wxT("invalid parameter") );
 130     wxCHECK_MSG( IsOpened(), 0, wxT("can't read from closed file") );
 131
 132     size_t nRead = fread(pBuf, 1, nCount, m_fp);
 133     if ( (nRead < nCount) && Error() )
 134     {
 135         wxLogSysError(_("Read error on file '%s'"), m_name.c_str());
 136     }
 137
 138     return nRead;
 139 }
 140
 141 size_t wxFFile::Write(const void *pBuf, size_t nCount)
 142 {
 143     wxCHECK_MSG( pBuf, 0, wxT("invalid parameter") );
 144     wxCHECK_MSG( IsOpened(), 0, wxT("can't write to closed file") );
 145
 146     size_t nWritten = fwrite(pBuf, 1, nCount, m_fp);
 147     if ( nWritten < nCount )
 148     {
 149         wxLogSysError(_("Write error on file '%s'"), m_name.c_str());
 150     }
 151
 152     return nWritten;
 153 }
 154
 155 bool wxFFile::Write(const wxString& s, const wxMBConv& conv)
 156 {
 157   const wxWX2MBbuf buf = s.mb_str(conv);
 158   if ( !buf )
 159       return false;
 160
 161   const size_t size = strlen(buf); // FIXME: use buf.length() when available
 162   return Write(buf, size) == size;
 163 }
 164
 165 bool wxFFile::Flush()
 166 {
 167     if ( IsOpened() )
 168     {
 169         if ( fflush(m_fp) != 0 )
 170         {
 171             wxLogSysError(_("failed to flush the file '%s'"), m_name.c_str());
 172
 173             return false;
 174         }
 175     }
 176
 177     return true;
 178 }
 179
 180 // ----------------------------------------------------------------------------
 181 // seeking
 182 // ----------------------------------------------------------------------------
 183
 184 bool wxFFile::Seek(wxFileOffset ofs, wxSeekMode mode)
 185 {
 186     wxCHECK_MSG( IsOpened(), false, wxT("can't seek on closed file") );
 187
 188     int origin;
 189     switch ( mode )
 190     {
 191         default:
 192             wxFAIL_MSG(wxT("unknown seek mode"));
 193             // still fall through
 194
 195         case wxFromStart:
 196             origin = SEEK_SET;
 197             break;
 198
 199         case wxFromCurrent:
 200             origin = SEEK_CUR;
 201             break;
 202
 203         case wxFromEnd:
 204             origin = SEEK_END;
 205             break;
 206     }
 207
 208 #ifndef wxHAS_LARGE_FFILES
 209     if ((long)ofs != ofs)
 210     {
 211         wxLogError(_("Seek error on file '%s' (large files not supported by stdio)"), m_name.c_str());
 212
 213         return false;
 214     }
 215
 216     if ( wxFseek(m_fp, (long)ofs, origin) != 0 )
 217 #else
 218     if ( wxFseek(m_fp, ofs, origin) != 0 )
 219 #endif
 220     {
 221         wxLogSysError(_("Seek error on file '%s'"), m_name.c_str());
 222
 223         return false;
 224     }
 225
 226     return true;
 227 }
 228
 229 wxFileOffset wxFFile::Tell() const
 230 {
 231     wxCHECK_MSG( IsOpened(), wxInvalidOffset,
 232                  wxT("wxFFile::Tell(): file is closed!") );
 233
 234     wxFileOffset rc = wxFtell(m_fp);
 235     if ( rc == wxInvalidOffset )
 236     {
 237         wxLogSysError(_("Can't find current position in file '%s'"),
 238                       m_name.c_str());
 239     }
 240
 241     return rc;
 242 }
 243
 244 wxFileOffset wxFFile::Length() const
 245 {
 246     wxCHECK_MSG( IsOpened(), wxInvalidOffset,
 247                  wxT("wxFFile::Length(): file is closed!") );
 248
 249     wxFFile& self = *const_cast<wxFFile *>(this);
 250
 251     wxFileOffset posOld = Tell();
 252     if ( posOld != wxInvalidOffset )
 253     {
 254         if ( self.SeekEnd() )
 255         {
 256             wxFileOffset len = Tell();
 257
 258             (void)self.Seek(posOld);
 259
 260             return len;
 261         }
 262     }
 263
 264     return wxInvalidOffset;
 265 }
 266
 267 #endif // wxUSE_FFILE