src/common/ffile.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/common/ffile.cpp
   3 // Purpose:     wxFFile encapsulates "FILE *" IO stream
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     14.07.99
   7 // Copyright:   (c) 1998 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
   8 // Licence:     wxWindows licence
   9 /////////////////////////////////////////////////////////////////////////////
  10
  11 // ============================================================================
  12 // declarations
  13 // ============================================================================
  14
  15 // ----------------------------------------------------------------------------
  16 // headers
  17 // ----------------------------------------------------------------------------
  18
  19 // For compilers that support precompilation, includes "wx.h".
  20 #include "wx/wxprec.h"
  21
  22 #ifdef __BORLANDC__
  23   #pragma hdrstop
  24 #endif
  25
  26 #if wxUSE_FFILE
  27
  28 #ifndef WX_PRECOMP
  29     #include "wx/intl.h"
  30     #include "wx/log.h"
  31     #include "wx/crt.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 // opening the file
  46 // ----------------------------------------------------------------------------
  47
  48 wxFFile::wxFFile(const wxString& filename, const wxString& mode)
  49 {
  50     Detach();
  51
  52     (void)Open(filename, mode);
  53 }
  54
  55 bool wxFFile::Open(const wxString& filename, const wxString& mode)
  56 {
  57     wxASSERT_MSG( !m_fp, wxT("should close or detach the old file first") );
  58
  59     m_fp = wxFopen(filename, mode);
  60
  61     if ( !m_fp )
  62     {
  63         wxLogSysError(_("can't open file '%s'"), filename);
  64
  65         return false;
  66     }
  67
  68     m_name = filename;
  69
  70     return true;
  71 }
  72
  73 bool wxFFile::Close()
  74 {
  75     if ( IsOpened() )
  76     {
  77         if ( fclose(m_fp) != 0 )
  78         {
  79             wxLogSysError(_("can't close file '%s'"), m_name.c_str());
  80
  81             return false;
  82         }
  83
  84         Detach();
  85     }
  86
  87     return true;
  88 }
  89
  90 // ----------------------------------------------------------------------------
  91 // read/write
  92 // ----------------------------------------------------------------------------
  93
  94 bool wxFFile::ReadAll(wxString *str, const wxMBConv& conv)
  95 {
  96     wxCHECK_MSG( str, false, wxT("invalid parameter") );
  97     wxCHECK_MSG( IsOpened(), false, wxT("can't read from closed file") );
  98     wxCHECK_MSG( Length() >= 0, false, wxT("invalid length") );
  99     size_t length = wx_truncate_cast(size_t, Length());
 100     wxCHECK_MSG( (wxFileOffset)length == Length(), false, wxT("huge file not supported") );
 101
 102     clearerr(m_fp);
 103
 104     wxCharBuffer buf(length);
 105
 106     // note that real length may be less than file length for text files with DOS EOLs
 107     // ('\r's get dropped by CRT when reading which means that we have
 108     // realLen = fileLen - numOfLinesInTheFile)
 109     length = fread(buf.data(), 1, length, m_fp);
 110
 111     if ( Error() )
 112     {
 113         wxLogSysError(_("Read error on file '%s'"), m_name.c_str());
 114
 115         return false;
 116     }
 117
 118     buf.data()[length] = 0;
 119
 120     wxString strTmp(buf, conv);
 121     str->swap(strTmp);
 122
 123     return true;
 124 }
 125
 126 size_t wxFFile::Read(void *pBuf, size_t nCount)
 127 {
 128     wxCHECK_MSG( pBuf, 0, wxT("invalid parameter") );
 129     wxCHECK_MSG( IsOpened(), 0, wxT("can't read from closed file") );
 130
 131     size_t nRead = fread(pBuf, 1, nCount, m_fp);
 132     if ( (nRead < nCount) && Error() )
 133     {
 134         wxLogSysError(_("Read error on file '%s'"), m_name.c_str());
 135     }
 136
 137     return nRead;
 138 }
 139
 140 size_t wxFFile::Write(const void *pBuf, size_t nCount)
 141 {
 142     wxCHECK_MSG( pBuf, 0, wxT("invalid parameter") );
 143     wxCHECK_MSG( IsOpened(), 0, wxT("can't write to closed file") );
 144
 145     size_t nWritten = fwrite(pBuf, 1, nCount, m_fp);
 146     if ( nWritten < nCount )
 147     {
 148         wxLogSysError(_("Write error on file '%s'"), m_name.c_str());
 149     }
 150
 151     return nWritten;
 152 }
 153
 154 bool wxFFile::Write(const wxString& s, const wxMBConv& conv)
 155 {
 156   const wxWX2MBbuf buf = s.mb_str(conv);
 157   if ( !buf )
 158       return false;
 159
 160   const size_t size = strlen(buf); // FIXME: use buf.length() when available
 161   return Write(buf, size) == size;
 162 }
 163
 164 bool wxFFile::Flush()
 165 {
 166     if ( IsOpened() )
 167     {
 168         if ( fflush(m_fp) != 0 )
 169         {
 170             wxLogSysError(_("failed to flush the file '%s'"), m_name.c_str());
 171
 172             return false;
 173         }
 174     }
 175
 176     return true;
 177 }
 178
 179 // ----------------------------------------------------------------------------
 180 // seeking
 181 // ----------------------------------------------------------------------------
 182
 183 bool wxFFile::Seek(wxFileOffset ofs, wxSeekMode mode)
 184 {
 185     wxCHECK_MSG( IsOpened(), false, wxT("can't seek on closed file") );
 186
 187     int origin;
 188     switch ( mode )
 189     {
 190         default:
 191             wxFAIL_MSG(wxT("unknown seek mode"));
 192             // still fall through
 193
 194         case wxFromStart:
 195             origin = SEEK_SET;
 196             break;
 197
 198         case wxFromCurrent:
 199             origin = SEEK_CUR;
 200             break;
 201
 202         case wxFromEnd:
 203             origin = SEEK_END;
 204             break;
 205     }
 206
 207 #ifndef wxHAS_LARGE_FFILES
 208     if ((long)ofs != ofs)
 209     {
 210         wxLogError(_("Seek error on file '%s' (large files not supported by stdio)"), m_name.c_str());
 211
 212         return false;
 213     }
 214
 215     if ( wxFseek(m_fp, (long)ofs, origin) != 0 )
 216 #else
 217     if ( wxFseek(m_fp, ofs, origin) != 0 )
 218 #endif
 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                  wxT("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                  wxT("wxFFile::Length(): file is closed!") );
 247
 248     wxFFile& self = *const_cast<wxFFile *>(this);
 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