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 // 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 + 1);
 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(), sizeof(char), 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     *str = wxString(buf, conv);
 121
 122     return true;
 123 }
 124
 125 size_t wxFFile::Read(void *pBuf, size_t nCount)
 126 {
 127     wxCHECK_MSG( pBuf, 0, wxT("invalid parameter") );
 128     wxCHECK_MSG( IsOpened(), 0, wxT("can't read from closed file") );
 129
 130     size_t nRead = fread(pBuf, 1, nCount, m_fp);
 131     if ( (nRead < nCount) && Error() )
 132     {
 133         wxLogSysError(_("Read error on file '%s'"), m_name.c_str());
 134     }
 135
 136     return nRead;
 137 }
 138
 139 size_t wxFFile::Write(const void *pBuf, size_t nCount)
 140 {
 141     wxCHECK_MSG( pBuf, 0, wxT("invalid parameter") );
 142     wxCHECK_MSG( IsOpened(), 0, wxT("can't write to closed file") );
 143
 144     size_t nWritten = fwrite(pBuf, 1, nCount, m_fp);
 145     if ( nWritten < nCount )
 146     {
 147         wxLogSysError(_("Write error on file '%s'"), m_name.c_str());
 148     }
 149
 150     return nWritten;
 151 }
 152
 153 bool wxFFile::Write(const wxString& s, const wxMBConv& conv)
 154 {
 155   const wxWX2MBbuf buf = s.mb_str(conv);
 156   if ( !buf )
 157       return false;
 158
 159   const size_t size = strlen(buf); // FIXME: use buf.length() when available
 160   return Write(buf, size) == size;
 161 }
 162
 163 bool wxFFile::Flush()
 164 {
 165     if ( IsOpened() )
 166     {
 167         if ( fflush(m_fp) != 0 )
 168         {
 169             wxLogSysError(_("failed to flush the file '%s'"), m_name.c_str());
 170
 171             return false;
 172         }
 173     }
 174
 175     return true;
 176 }
 177
 178 // ----------------------------------------------------------------------------
 179 // seeking
 180 // ----------------------------------------------------------------------------
 181
 182 bool wxFFile::Seek(wxFileOffset ofs, wxSeekMode mode)
 183 {
 184     wxCHECK_MSG( IsOpened(), false, wxT("can't seek on closed file") );
 185
 186     int origin;
 187     switch ( mode )
 188     {
 189         default:
 190             wxFAIL_MSG(wxT("unknown seek mode"));
 191             // still fall through
 192
 193         case wxFromStart:
 194             origin = SEEK_SET;
 195             break;
 196
 197         case wxFromCurrent:
 198             origin = SEEK_CUR;
 199             break;
 200
 201         case wxFromEnd:
 202             origin = SEEK_END;
 203             break;
 204     }
 205
 206 #ifndef wxHAS_LARGE_FFILES
 207     if ((long)ofs != ofs)
 208     {
 209         wxLogError(_("Seek error on file '%s' (large files not supported by stdio)"), m_name.c_str());
 210
 211         return false;
 212     }
 213
 214     if ( wxFseek(m_fp, (long)ofs, origin) != 0 )
 215 #else
 216     if ( wxFseek(m_fp, ofs, origin) != 0 )
 217 #endif
 218     {
 219         wxLogSysError(_("Seek error on file '%s'"), m_name.c_str());
 220
 221         return false;
 222     }
 223
 224     return true;
 225 }
 226
 227 wxFileOffset wxFFile::Tell() const
 228 {
 229     wxCHECK_MSG( IsOpened(), wxInvalidOffset,
 230                  wxT("wxFFile::Tell(): file is closed!") );
 231
 232     wxFileOffset rc = wxFtell(m_fp);
 233     if ( rc == wxInvalidOffset )
 234     {
 235         wxLogSysError(_("Can't find current position in file '%s'"),
 236                       m_name.c_str());
 237     }
 238
 239     return rc;
 240 }
 241
 242 wxFileOffset wxFFile::Length() const
 243 {
 244     wxCHECK_MSG( IsOpened(), wxInvalidOffset,
 245                  wxT("wxFFile::Length(): file is closed!") );
 246
 247     wxFFile& self = *const_cast<wxFFile *>(this);
 248
 249     wxFileOffset posOld = Tell();
 250     if ( posOld != wxInvalidOffset )
 251     {
 252         if ( self.SeekEnd() )
 253         {
 254             wxFileOffset len = Tell();
 255
 256             (void)self.Seek(posOld);
 257
 258             return len;
 259         }
 260     }
 261
 262     return wxInvalidOffset;
 263 }
 264
 265 #endif // wxUSE_FFILE