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 license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 // ----------------------------------------------------------------------------
  17 // headers
  18 // ----------------------------------------------------------------------------
  19
  20 #ifdef __GNUG__
  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_FILE
  32
  33 #ifndef WX_PRECOMP
  34 #endif
  35
  36 #include "wx/ffile.h"
  37
  38 // ============================================================================
  39 // implementation
  40 // ============================================================================
  41
  42 // ----------------------------------------------------------------------------
  43 // opening the file
  44 // ----------------------------------------------------------------------------
  45
  46 wxFFile::wxFFile(const wxChar *filename, const char *mode)
  47 {
  48     Detach();
  49
  50     (void)Open(filename, mode);
  51 }
  52
  53 bool wxFFile::Open(const wxChar *filename, const char *mode)
  54 {
  55     wxASSERT_MSG( !m_fp, _T("should close or detach the old file first") );
  56
  57     m_fp = fopen(filename, mode);
  58
  59     if ( !m_fp )
  60     {
  61         wxLogSysError(_("can't open file '%s'"), filename);
  62
  63         return FALSE;
  64     }
  65
  66     m_name = filename;
  67
  68     return TRUE;
  69 }
  70
  71 bool wxFFile::Close()
  72 {
  73     if ( IsOpened() )
  74     {
  75         if ( !fclose(m_fp) )
  76         {
  77             wxLogSysError(_("can't close file '%s'"), m_name.c_str());
  78
  79             return FALSE;
  80         }
  81
  82         Detach();
  83     }
  84
  85     return TRUE;
  86 }
  87
  88 // ----------------------------------------------------------------------------
  89 // read/write
  90 // ----------------------------------------------------------------------------
  91
  92 bool wxFFile::ReadAll(wxString *str)
  93 {
  94     wxCHECK_MSG( str, FALSE, _T("invalid parameter") );
  95     wxCHECK_MSG( IsOpened(), FALSE, _T("can't read from closed file") );
  96
  97     clearerr(m_fp);
  98
  99     str->Empty();
 100     str->Alloc(Length());
 101
 102     wxChar buf[1024];
 103     static const size_t nSize = WXSIZEOF(buf) - 1; // -1 for trailing '\0'
 104     while ( !Eof() )
 105     {
 106         size_t nRead = fread(buf, sizeof(wxChar), nSize, m_fp);
 107         if ( (nRead < nSize) && Error() )
 108         {
 109             wxLogSysError(_("Read error on file '%s'"), m_name.c_str());
 110
 111             return FALSE;
 112         }
 113         //else: just EOF
 114
 115         buf[nRead] = 0;
 116         *str += buf;
 117     }
 118
 119     return TRUE;
 120 }
 121
 122 size_t wxFFile::Read(void *pBuf, size_t nCount)
 123 {
 124     wxCHECK_MSG( pBuf, FALSE, _T("invalid parameter") );
 125     wxCHECK_MSG( IsOpened(), FALSE, _T("can't read from closed file") );
 126
 127     size_t nRead = fread(pBuf, 1, nCount, m_fp);
 128     if ( (nRead < nCount) && Error() )
 129     {
 130         wxLogSysError(_("Read error on file '%s'"), m_name.c_str());
 131     }
 132
 133     return nRead;
 134 }
 135
 136 size_t wxFFile::Write(const void *pBuf, size_t nCount)
 137 {
 138     wxCHECK_MSG( pBuf, FALSE, _T("invalid parameter") );
 139     wxCHECK_MSG( IsOpened(), FALSE, _T("can't write to closed file") );
 140
 141     size_t nWritten = fwrite(pBuf, 1, nCount, m_fp);
 142     if ( nWritten < nCount )
 143     {
 144         wxLogSysError(_("Write error on file '%s'"), m_name.c_str());
 145     }
 146
 147     return nWritten;
 148 }
 149
 150 bool wxFFile::Flush()
 151 {
 152     if ( IsOpened() )
 153     {
 154         if ( !fflush(m_fp) )
 155         {
 156             wxLogSysError(_("failed to flush the file '%s'"), m_name.c_str());
 157
 158             return FALSE;
 159         }
 160     }
 161
 162     return TRUE;
 163 }
 164
 165 // ----------------------------------------------------------------------------
 166 // seeking
 167 // ----------------------------------------------------------------------------
 168
 169 bool wxFFile::Seek(long ofs, wxSeekMode mode)
 170 {
 171     wxCHECK_MSG( IsOpened(), FALSE, _T("can't seek on closed file") );
 172
 173     int origin;
 174     switch ( mode )
 175     {
 176         default:
 177             wxFAIL_MSG(_T("unknown seek mode"));
 178             // still fall through
 179
 180         case wxFromStart:
 181             origin = SEEK_SET;
 182             break;
 183
 184         case wxFromCurrent:
 185             origin = SEEK_CUR;
 186             break;
 187
 188         case wxFromEnd:
 189             origin = SEEK_END;
 190             break;
 191     }
 192
 193     if ( fseek(m_fp, ofs, origin) != 0 )
 194     {
 195         wxLogSysError(_("Seek error on file '%s'"), m_name.c_str());
 196
 197         return FALSE;
 198     }
 199
 200     return TRUE;
 201 }
 202
 203 size_t wxFFile::Tell() const
 204 {
 205     long rc = ftell(m_fp);
 206     if ( rc == -1 )
 207     {
 208         wxLogSysError(_("Can't find current position in file '%s'"),
 209                       m_name.c_str());
 210     }
 211
 212     return (size_t)rc;
 213 }
 214
 215 size_t wxFFile::Length() const
 216 {
 217     wxFFile& self = *(wxFFile *)this;   // const_cast
 218
 219     size_t posOld = Tell();
 220     if ( posOld != (size_t)-1 )
 221     {
 222         if ( self.SeekEnd() )
 223         {
 224             size_t len = Tell();
 225
 226             (void)self.Seek(posOld);
 227
 228             return len;
 229         }
 230     }
 231
 232     return (size_t)-1;
 233 }
 234
 235 #endif // wxUSE_FILE