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)
 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( length == Length(), false, wxT("huge file not supported") );
 113
 114     clearerr(m_fp);
 115
 116     str->Empty();
 117     str->Alloc(length);
 118
 119     wxChar buf[1024];
 120     static const size_t nSize = WXSIZEOF(buf) - 1; // -1 for trailing '\0'
 121     while ( !Eof() )
 122     {
 123         size_t nRead = fread(buf, sizeof(wxChar), nSize, m_fp);
 124         if ( (nRead < nSize) && Error() )
 125         {
 126             wxLogSysError(_("Read error on file '%s'"), m_name.c_str());
 127
 128             return false;
 129         }
 130         //else: just EOF
 131
 132         buf[nRead] = 0;
 133         *str += buf;
 134     }
 135
 136     return true;
 137 }
 138
 139 size_t wxFFile::Read(void *pBuf, size_t nCount)
 140 {
 141     wxCHECK_MSG( pBuf, FALSE, wxT("invalid parameter") );
 142     wxCHECK_MSG( IsOpened(), FALSE, wxT("can't read from closed file") );
 143
 144     size_t nRead = fread(pBuf, 1, nCount, m_fp);
 145     if ( (nRead < nCount) && Error() )
 146     {
 147         wxLogSysError(_("Read error on file '%s'"), m_name.c_str());
 148     }
 149
 150     return nRead;
 151 }
 152
 153 size_t wxFFile::Write(const void *pBuf, size_t nCount)
 154 {
 155     wxCHECK_MSG( pBuf, FALSE, wxT("invalid parameter") );
 156     wxCHECK_MSG( IsOpened(), FALSE, wxT("can't write to closed file") );
 157
 158     size_t nWritten = fwrite(pBuf, 1, nCount, m_fp);
 159     if ( nWritten < nCount )
 160     {
 161         wxLogSysError(_("Write error on file '%s'"), m_name.c_str());
 162     }
 163
 164     return nWritten;
 165 }
 166
 167 bool wxFFile::Flush()
 168 {
 169     if ( IsOpened() )
 170     {
 171         // fflush returns non-zero on error
 172         //
 173         if ( fflush(m_fp) )
 174         {
 175             wxLogSysError(_("failed to flush the file '%s'"), m_name.c_str());
 176
 177             return false;
 178         }
 179     }
 180
 181     return true;
 182 }
 183
 184 // ----------------------------------------------------------------------------
 185 // seeking
 186 // ----------------------------------------------------------------------------
 187
 188 bool wxFFile::Seek(wxFileOffset ofs, wxSeekMode mode)
 189 {
 190     wxCHECK_MSG( IsOpened(), false, wxT("can't seek on closed file") );
 191
 192     int origin;
 193     switch ( mode )
 194     {
 195         default:
 196             wxFAIL_MSG(wxT("unknown seek mode"));
 197             // still fall through
 198
 199         case wxFromStart:
 200             origin = SEEK_SET;
 201             break;
 202
 203         case wxFromCurrent:
 204             origin = SEEK_CUR;
 205             break;
 206
 207         case wxFromEnd:
 208             origin = SEEK_END;
 209             break;
 210     }
 211
 212 #ifndef HAVE_FSEEKO
 213     if ((long)ofs != ofs)
 214     {
 215         wxLogError(_("Seek error on file '%s' (large files not supported by stdio)"), m_name.c_str());
 216
 217         return false;
 218     }
 219
 220     if ( wxFseek(m_fp, (long)ofs, origin) != 0 )
 221 #else
 222     if ( wxFseek(m_fp, ofs, origin) != 0 )
 223 #endif
 224     {
 225         wxLogSysError(_("Seek error on file '%s'"), m_name.c_str());
 226
 227         return false;
 228     }
 229
 230     return true;
 231 }
 232
 233 wxFileOffset wxFFile::Tell() const
 234 {
 235     wxCHECK_MSG( IsOpened(), wxInvalidOffset,
 236                  _T("wxFFile::Tell(): file is closed!") );
 237
 238     wxFileOffset rc = wxFtell(m_fp);
 239     if ( rc == wxInvalidOffset )
 240     {
 241         wxLogSysError(_("Can't find current position in file '%s'"),
 242                       m_name.c_str());
 243     }
 244
 245     return rc;
 246 }
 247
 248 wxFileOffset wxFFile::Length() const
 249 {
 250     wxCHECK_MSG( IsOpened(), wxInvalidOffset,
 251                  _T("wxFFile::Length(): file is closed!") );
 252
 253     wxFFile& self = *(wxFFile *)this;   // const_cast
 254
 255     wxFileOffset posOld = Tell();
 256     if ( posOld != wxInvalidOffset )
 257     {
 258         if ( self.SeekEnd() )
 259         {
 260             wxFileOffset len = Tell();
 261
 262             (void)self.Seek(posOld);
 263
 264             return len;
 265         }
 266     }
 267
 268     return wxInvalidOffset;
 269 }
 270
 271 #endif // wxUSE_FFILE