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 // opening the file
  46 // ----------------------------------------------------------------------------
  47
  48 wxFFile::wxFFile(const wxChar *filename, const wxChar *mode)
  49 {
  50     Detach();
  51
  52     (void)Open(filename, mode);
  53 }
  54
  55 bool wxFFile::Open(const wxChar *filename, const wxChar *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)
  95 {
  96     wxCHECK_MSG( str, false, wxT("invalid parameter") );
  97     wxCHECK_MSG( IsOpened(), false, wxT("can't read from closed file") );
  98
  99     clearerr(m_fp);
 100
 101     str->Empty();
 102     str->Alloc(Length());
 103
 104     wxChar buf[1024];
 105     static const size_t nSize = WXSIZEOF(buf) - 1; // -1 for trailing '\0'
 106     while ( !Eof() )
 107     {
 108         size_t nRead = fread(buf, sizeof(wxChar), nSize, m_fp);
 109         if ( (nRead < nSize) && Error() )
 110         {
 111             wxLogSysError(_("Read error on file '%s'"), m_name.c_str());
 112
 113             return false;
 114         }
 115         //else: just EOF
 116
 117         buf[nRead] = 0;
 118         *str += buf;
 119     }
 120
 121     return true;
 122 }
 123
 124 size_t wxFFile::Read(void *pBuf, size_t nCount)
 125 {
 126     wxCHECK_MSG( pBuf, FALSE, wxT("invalid parameter") );
 127     wxCHECK_MSG( IsOpened(), FALSE, wxT("can't read from closed file") );
 128
 129     size_t nRead = fread(pBuf, 1, nCount, m_fp);
 130     if ( (nRead < nCount) && Error() )
 131     {
 132         wxLogSysError(_("Read error on file '%s'"), m_name.c_str());
 133     }
 134
 135     return nRead;
 136 }
 137
 138 size_t wxFFile::Write(const void *pBuf, size_t nCount)
 139 {
 140     wxCHECK_MSG( pBuf, FALSE, wxT("invalid parameter") );
 141     wxCHECK_MSG( IsOpened(), FALSE, wxT("can't write to closed file") );
 142
 143     size_t nWritten = fwrite(pBuf, 1, nCount, m_fp);
 144     if ( nWritten < nCount )
 145     {
 146         wxLogSysError(_("Write error on file '%s'"), m_name.c_str());
 147     }
 148
 149     return nWritten;
 150 }
 151
 152 bool wxFFile::Flush()
 153 {
 154     if ( IsOpened() )
 155     {
 156         // fflush returns non-zero on error
 157         //
 158         if ( fflush(m_fp) )
 159         {
 160             wxLogSysError(_("failed to flush the file '%s'"), m_name.c_str());
 161
 162             return false;
 163         }
 164     }
 165
 166     return true;
 167 }
 168
 169 // ----------------------------------------------------------------------------
 170 // seeking
 171 // ----------------------------------------------------------------------------
 172
 173 bool wxFFile::Seek(long ofs, wxSeekMode mode)
 174 {
 175     wxCHECK_MSG( IsOpened(), false, wxT("can't seek on closed file") );
 176
 177     int origin;
 178     switch ( mode )
 179     {
 180         default:
 181             wxFAIL_MSG(wxT("unknown seek mode"));
 182             // still fall through
 183
 184         case wxFromStart:
 185             origin = SEEK_SET;
 186             break;
 187
 188         case wxFromCurrent:
 189             origin = SEEK_CUR;
 190             break;
 191
 192         case wxFromEnd:
 193             origin = SEEK_END;
 194             break;
 195     }
 196
 197     if ( fseek(m_fp, ofs, origin) != 0 )
 198     {
 199         wxLogSysError(_("Seek error on file '%s'"), m_name.c_str());
 200
 201         return false;
 202     }
 203
 204     return true;
 205 }
 206
 207 size_t wxFFile::Tell() const
 208 {
 209     wxCHECK_MSG( IsOpened(), (size_t)-1,
 210                  _T("wxFFile::Tell(): file is closed!") );
 211
 212     long rc = ftell(m_fp);
 213     if ( rc == -1 )
 214     {
 215         wxLogSysError(_("Can't find current position in file '%s'"),
 216                       m_name.c_str());
 217     }
 218
 219     return (size_t)rc;
 220 }
 221
 222 size_t wxFFile::Length() const
 223 {
 224     wxCHECK_MSG( IsOpened(), (size_t)-1,
 225                  _T("wxFFile::Length(): file is closed!") );
 226
 227     wxFFile& self = *(wxFFile *)this;   // const_cast
 228
 229     size_t posOld = Tell();
 230     if ( posOld != (size_t)-1 )
 231     {
 232         if ( self.SeekEnd() )
 233         {
 234             size_t len = Tell();
 235
 236             (void)self.Seek(posOld);
 237
 238             return len;
 239         }
 240     }
 241
 242     return (size_t)-1;
 243 }
 244
 245 #endif // wxUSE_FFILE