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     if ( (fread(buf.data(), sizeof(char), fileLen, m_fp) < fileLen) || Error() )
 119     {
 120         wxLogSysError(_("Read error on file '%s'"), m_name.c_str());
 121
 122         return false;
 123     }
 124
 125     buf.data()[fileLen] = 0;
 126     *str = wxString(buf, conv);
 127
 128     return true;
 129 }
 130
 131 size_t wxFFile::Read(void *pBuf, size_t nCount)
 132 {
 133     wxCHECK_MSG( pBuf, FALSE, wxT("invalid parameter") );
 134     wxCHECK_MSG( IsOpened(), FALSE, wxT("can't read from closed file") );
 135
 136     size_t nRead = fread(pBuf, 1, nCount, m_fp);
 137     if ( (nRead < nCount) && Error() )
 138     {
 139         wxLogSysError(_("Read error on file '%s'"), m_name.c_str());
 140     }
 141
 142     return nRead;
 143 }
 144
 145 size_t wxFFile::Write(const void *pBuf, size_t nCount)
 146 {
 147     wxCHECK_MSG( pBuf, FALSE, wxT("invalid parameter") );
 148     wxCHECK_MSG( IsOpened(), FALSE, wxT("can't write to closed file") );
 149
 150     size_t nWritten = fwrite(pBuf, 1, nCount, m_fp);
 151     if ( nWritten < nCount )
 152     {
 153         wxLogSysError(_("Write error on file '%s'"), m_name.c_str());
 154     }
 155
 156     return nWritten;
 157 }
 158
 159 bool wxFFile::Flush()
 160 {
 161     if ( IsOpened() )
 162     {
 163         // fflush returns non-zero on error
 164         //
 165         if ( fflush(m_fp) )
 166         {
 167             wxLogSysError(_("failed to flush the file '%s'"), m_name.c_str());
 168
 169             return false;
 170         }
 171     }
 172
 173     return true;
 174 }
 175
 176 // ----------------------------------------------------------------------------
 177 // seeking
 178 // ----------------------------------------------------------------------------
 179
 180 bool wxFFile::Seek(wxFileOffset ofs, wxSeekMode mode)
 181 {
 182     wxCHECK_MSG( IsOpened(), false, wxT("can't seek on closed file") );
 183
 184     int origin;
 185     switch ( mode )
 186     {
 187         default:
 188             wxFAIL_MSG(wxT("unknown seek mode"));
 189             // still fall through
 190
 191         case wxFromStart:
 192             origin = SEEK_SET;
 193             break;
 194
 195         case wxFromCurrent:
 196             origin = SEEK_CUR;
 197             break;
 198
 199         case wxFromEnd:
 200             origin = SEEK_END;
 201             break;
 202     }
 203
 204 #ifndef HAVE_FSEEKO
 205     if ((long)ofs != ofs)
 206     {
 207         wxLogError(_("Seek error on file '%s' (large files not supported by stdio)"), m_name.c_str());
 208
 209         return false;
 210     }
 211
 212     if ( wxFseek(m_fp, (long)ofs, origin) != 0 )
 213 #else
 214     if ( wxFseek(m_fp, ofs, origin) != 0 )
 215 #endif
 216     {
 217         wxLogSysError(_("Seek error on file '%s'"), m_name.c_str());
 218
 219         return false;
 220     }
 221
 222     return true;
 223 }
 224
 225 wxFileOffset wxFFile::Tell() const
 226 {
 227     wxCHECK_MSG( IsOpened(), wxInvalidOffset,
 228                  _T("wxFFile::Tell(): file is closed!") );
 229
 230     wxFileOffset rc = wxFtell(m_fp);
 231     if ( rc == wxInvalidOffset )
 232     {
 233         wxLogSysError(_("Can't find current position in file '%s'"),
 234                       m_name.c_str());
 235     }
 236
 237     return rc;
 238 }
 239
 240 wxFileOffset wxFFile::Length() const
 241 {
 242     wxCHECK_MSG( IsOpened(), wxInvalidOffset,
 243                  _T("wxFFile::Length(): file is closed!") );
 244
 245     wxFFile& self = *(wxFFile *)this;   // const_cast
 246
 247     wxFileOffset posOld = Tell();
 248     if ( posOld != wxInvalidOffset )
 249     {
 250         if ( self.SeekEnd() )
 251         {
 252             wxFileOffset len = Tell();
 253
 254             (void)self.Seek(posOld);
 255
 256             return len;
 257         }
 258     }
 259
 260     return wxInvalidOffset;
 261 }
 262
 263 #endif // wxUSE_FFILE