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 #endif
  33
  34 #ifdef __WINDOWS__
  35 #include "wx/msw/mslu.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, const 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 = wx_truncate_cast(size_t, Length());
 112     wxCHECK_MSG( (wxFileOffset)length == Length(), false, wxT("huge file not supported") );
 113
 114     clearerr(m_fp);
 115
 116     wxCharBuffer buf(length + 1);
 117
 118     // note that real length may be less than file length for text files with DOS EOLs
 119     // ('\r's get dropped by CRT when reading which means that we have
 120     // realLen = fileLen - numOfLinesInTheFile)
 121     length = fread(buf.data(), sizeof(char), length, m_fp);
 122
 123     if ( Error() )
 124     {
 125         wxLogSysError(_("Read error on file '%s'"), m_name.c_str());
 126
 127         return false;
 128     }
 129
 130     buf.data()[length] = 0;
 131     *str = wxString(buf, conv);
 132
 133     return true;
 134 }
 135
 136 size_t wxFFile::Read(void *pBuf, size_t nCount)
 137 {
 138     wxCHECK_MSG( pBuf, 0, wxT("invalid parameter") );
 139     wxCHECK_MSG( IsOpened(), 0, 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, 0, wxT("invalid parameter") );
 153     wxCHECK_MSG( IsOpened(), 0, 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::Write(const wxString& s, const wxMBConv& conv)
 165 {
 166   const wxWX2MBbuf buf = s.mb_str(conv);
 167   if ( !buf )
 168       return false;
 169
 170   const size_t size = strlen(buf); // FIXME: use buf.length() when available
 171   return Write(buf, size) == size;
 172 }
 173
 174 bool wxFFile::Flush()
 175 {
 176     if ( IsOpened() )
 177     {
 178         if ( fflush(m_fp) != 0 )
 179         {
 180             wxLogSysError(_("failed to flush the file '%s'"), m_name.c_str());
 181
 182             return false;
 183         }
 184     }
 185
 186     return true;
 187 }
 188
 189 // ----------------------------------------------------------------------------
 190 // seeking
 191 // ----------------------------------------------------------------------------
 192
 193 bool wxFFile::Seek(wxFileOffset ofs, wxSeekMode mode)
 194 {
 195     wxCHECK_MSG( IsOpened(), false, wxT("can't seek on closed file") );
 196
 197     int origin;
 198     switch ( mode )
 199     {
 200         default:
 201             wxFAIL_MSG(wxT("unknown seek mode"));
 202             // still fall through
 203
 204         case wxFromStart:
 205             origin = SEEK_SET;
 206             break;
 207
 208         case wxFromCurrent:
 209             origin = SEEK_CUR;
 210             break;
 211
 212         case wxFromEnd:
 213             origin = SEEK_END;
 214             break;
 215     }
 216
 217 #ifndef HAVE_FSEEKO
 218     if ((long)ofs != ofs)
 219     {
 220         wxLogError(_("Seek error on file '%s' (large files not supported by stdio)"), m_name.c_str());
 221
 222         return false;
 223     }
 224
 225     if ( wxFseek(m_fp, (long)ofs, origin) != 0 )
 226 #else
 227     if ( wxFseek(m_fp, ofs, origin) != 0 )
 228 #endif
 229     {
 230         wxLogSysError(_("Seek error on file '%s'"), m_name.c_str());
 231
 232         return false;
 233     }
 234
 235     return true;
 236 }
 237
 238 wxFileOffset wxFFile::Tell() const
 239 {
 240     wxCHECK_MSG( IsOpened(), wxInvalidOffset,
 241                  _T("wxFFile::Tell(): file is closed!") );
 242
 243     wxFileOffset rc = wxFtell(m_fp);
 244     if ( rc == wxInvalidOffset )
 245     {
 246         wxLogSysError(_("Can't find current position in file '%s'"),
 247                       m_name.c_str());
 248     }
 249
 250     return rc;
 251 }
 252
 253 wxFileOffset wxFFile::Length() const
 254 {
 255     wxCHECK_MSG( IsOpened(), wxInvalidOffset,
 256                  _T("wxFFile::Length(): file is closed!") );
 257
 258     wxFFile& self = *(wxFFile *)this;   // const_cast
 259
 260     wxFileOffset posOld = Tell();
 261     if ( posOld != wxInvalidOffset )
 262     {
 263         if ( self.SeekEnd() )
 264         {
 265             wxFileOffset len = Tell();
 266
 267             (void)self.Seek(posOld);
 268
 269             return len;
 270         }
 271     }
 272
 273     return wxInvalidOffset;
 274 }
 275
 276 #endif // wxUSE_FFILE