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
 111     clearerr(m_fp);
 112
 113     str->Empty();
 114     str->Alloc(Length());
 115
 116     wxChar buf[1024];
 117     static const size_t nSize = WXSIZEOF(buf) - 1; // -1 for trailing '\0'
 118     while ( !Eof() )
 119     {
 120         size_t nRead = fread(buf, sizeof(wxChar), nSize, m_fp);
 121         if ( (nRead < nSize) && Error() )
 122         {
 123             wxLogSysError(_("Read error on file '%s'"), m_name.c_str());
 124
 125             return false;
 126         }
 127         //else: just EOF
 128
 129         buf[nRead] = 0;
 130         *str += buf;
 131     }
 132
 133     return true;
 134 }
 135
 136 size_t wxFFile::Read(void *pBuf, size_t nCount)
 137 {
 138     wxCHECK_MSG( pBuf, FALSE, wxT("invalid parameter") );
 139     wxCHECK_MSG( IsOpened(), FALSE, wxT("can't read from closed file") );
 140
 141     size_t nRead = fread(pBuf, 1, nCount, m_fp);
 142     if ( (nRead < nCount) && Error() )
 143     {
 144         wxLogSysError(_("Read error on file '%s'"), m_name.c_str());
 145     }
 146
 147     return nRead;
 148 }
 149
 150 size_t wxFFile::Write(const void *pBuf, size_t nCount)
 151 {
 152     wxCHECK_MSG( pBuf, FALSE, wxT("invalid parameter") );
 153     wxCHECK_MSG( IsOpened(), FALSE, wxT("can't write to closed file") );
 154
 155     size_t nWritten = fwrite(pBuf, 1, nCount, m_fp);
 156     if ( nWritten < nCount )
 157     {
 158         wxLogSysError(_("Write error on file '%s'"), m_name.c_str());
 159     }
 160
 161     return nWritten;
 162 }
 163
 164 bool wxFFile::Flush()
 165 {
 166     if ( IsOpened() )
 167     {
 168         // fflush returns non-zero on error
 169         //
 170         if ( fflush(m_fp) )
 171         {
 172             wxLogSysError(_("failed to flush the file '%s'"), m_name.c_str());
 173
 174             return false;
 175         }
 176     }
 177
 178     return true;
 179 }
 180
 181 // ----------------------------------------------------------------------------
 182 // seeking
 183 // ----------------------------------------------------------------------------
 184
 185 bool wxFFile::Seek(wxFileOffset ofs, wxSeekMode mode)
 186 {
 187     wxCHECK_MSG( IsOpened(), false, wxT("can't seek on closed file") );
 188
 189     int origin;
 190     switch ( mode )
 191     {
 192         default:
 193             wxFAIL_MSG(wxT("unknown seek mode"));
 194             // still fall through
 195
 196         case wxFromStart:
 197             origin = SEEK_SET;
 198             break;
 199
 200         case wxFromCurrent:
 201             origin = SEEK_CUR;
 202             break;
 203
 204         case wxFromEnd:
 205             origin = SEEK_END;
 206             break;
 207     }
 208
 209 #ifndef HAVE_FSEEKO
 210     if ((long)ofs != ofs)
 211     {
 212         wxLogError(_("Seek error on file '%s' (large files not supported by stdio)"), m_name.c_str());
 213
 214         return false;
 215     }
 216 #endif
 217
 218     if ( wxFseek(m_fp, ofs, origin) != 0 )
 219     {
 220         wxLogSysError(_("Seek error on file '%s'"), m_name.c_str());
 221
 222         return false;
 223     }
 224
 225     return true;
 226 }
 227
 228 wxFileOffset wxFFile::Tell() const
 229 {
 230     wxCHECK_MSG( IsOpened(), wxInvalidOffset,
 231                  _T("wxFFile::Tell(): file is closed!") );
 232
 233     wxFileOffset rc = wxFtell(m_fp);
 234     if ( rc == wxInvalidOffset )
 235     {
 236         wxLogSysError(_("Can't find current position in file '%s'"),
 237                       m_name.c_str());
 238     }
 239
 240     return rc;
 241 }
 242
 243 wxFileOffset wxFFile::Length() const
 244 {
 245     wxCHECK_MSG( IsOpened(), wxInvalidOffset,
 246                  _T("wxFFile::Length(): file is closed!") );
 247
 248     wxFFile& self = *(wxFFile *)this;   // const_cast
 249
 250     wxFileOffset posOld = Tell();
 251     if ( posOld != wxInvalidOffset )
 252     {
 253         if ( self.SeekEnd() )
 254         {
 255             wxFileOffset len = Tell();
 256
 257             (void)self.Seek(posOld);
 258
 259             return len;
 260         }
 261     }
 262
 263     return wxInvalidOffset;
 264 }
 265
 266 #endif // wxUSE_FFILE