src/add-ons/media/plugins/matroska/libebml/StdIOCallback.cpp

   1 /****************************************************************************
   2 ** libebml : parse EBML files, see http://embl.sourceforge.net/
   3 **
   4 ** <file/class description>
   5 **
   6 ** Copyright (C) 2002-2004 Ingo Ralf Blum.  All rights reserved.
   7 **
   8 ** This library is free software; you can redistribute it and/or
   9 ** modify it under the terms of the GNU Lesser General Public
  10 ** License as published by the Free Software Foundation; either
  11 ** version 2.1 of the License, or (at your option) any later version.
  12 **
  13 ** This library is distributed in the hope that it will be useful,
  14 ** but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16 ** Lesser General Public License for more details.
  17 **
  18 ** You should have received a copy of the GNU Lesser General Public
  19 ** License along with this library; if not, write to the Free Software
  20 ** Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21 **
  22 ** See http://www.matroska.org/license/lgpl/ for LGPL licensing information.
  23 **
  24 ** Contact license@matroska.org if any conditions of this licensing are
  25 ** not clear to you.
  26 **
  27 **********************************************************************/
  28
  29 /*!
  30         \file
  31         \version \$Id: StdIOCallback.cpp 1298 2008-02-21 22:14:18Z mosu $
  32         \author Steve Lhomme     <robux4 @ users.sf.net>
  33         \author Moritz Bunkus <moritz @ bunkus.org>
  34 */
  35
  36 #include <cassert>
  37 #include <climits>
  38 #if !defined(__GNUC__) || (__GNUC__ > 2)
  39 #include <sstream>
  40 #endif // GCC2
  41
  42 #include "ebml/StdIOCallback.h"
  43 #include "ebml/Debug.h"
  44 #include "ebml/EbmlConfig.h"
  45
  46 using namespace std;
  47
  48 START_LIBEBML_NAMESPACE
  49
  50 CRTError::CRTError(int nError, const std::string & Description)
  51         :std::runtime_error(Description+": "+strerror(nError))
  52         ,Error(Error)
  53 {
  54 }
  55
  56 CRTError::CRTError(const std::string & Description,int nError)
  57         :std::runtime_error(Description+": "+strerror(nError))
  58         ,Error(Error)
  59 {
  60 }
  61
  62
  63 StdIOCallback::StdIOCallback(const char*Path, const open_mode aMode)
  64 {
  65         assert(Path!=0);
  66
  67         const char *Mode;
  68         switch (aMode)
  69         {
  70         case MODE_READ:
  71                 Mode = "rb";
  72                 break;
  73         case MODE_SAFE:
  74                 Mode = "rb+";
  75                 break;
  76         case MODE_WRITE:
  77                 Mode = "wb";
  78                 break;
  79         case MODE_CREATE:
  80                 Mode = "wb+";
  81                 break;
  82         default:
  83                 throw 0;
  84         }
  85
  86         File=fopen(Path,Mode);
  87         if(File==0)
  88         {
  89 #if !defined(__GNUC__) || (__GNUC__ > 2)
  90                 stringstream Msg;
  91                 Msg<<"Can't open stdio file \""<<Path<<"\" in mode \""<<Mode<<"\"";
  92                 throw CRTError(Msg.str());
  93 #endif // GCC2
  94         }
  95         mCurrentPosition = 0;
  96 }
  97
  98
  99 StdIOCallback::~StdIOCallback()throw()
 100 {
 101         close();
 102 }
 103
 104
 105
 106 uint32 StdIOCallback::read(void*Buffer,size_t Size)
 107 {
 108         assert(File!=0);
 109
 110         size_t result = fread(Buffer, 1, Size, File);
 111         mCurrentPosition += result;
 112         return result;
 113 }
 114
 115 void StdIOCallback::setFilePointer(int64 Offset,seek_mode Mode)
 116 {
 117         assert(File!=0);
 118
 119         // There is a numeric cast in the boost library, which would be quite nice for this checking
 120 /*
 121         SL : replaced because unknown class in cygwin
 122         assert(Offset <= numeric_limits<long>::max());
 123         assert(Offset >= numeric_limits<long>::min());
 124 */
 125
 126         assert(Offset <= LONG_MAX);
 127         assert(Offset >= LONG_MIN);
 128
 129         assert(Mode==SEEK_CUR||Mode==SEEK_END||Mode==SEEK_SET);
 130
 131         if(fseek(File,Offset,Mode)!=0)
 132         {
 133 #if !defined(__GNUC__) || (__GNUC__ > 2)
 134                 ostringstream Msg;
 135                 Msg<<"Failed to seek file "<<File<<" to offset "<<(unsigned long)Offset<<" in mode "<<Mode;
 136                 throw CRTError(Msg.str());
 137 #endif // GCC2
 138                 mCurrentPosition = ftell(File);
 139         }
 140         else
 141         {
 142                 switch ( Mode )
 143                 {
 144                         case SEEK_CUR:
 145                                 mCurrentPosition += Offset;
 146                                 break;
 147                         case SEEK_END:
 148                                 mCurrentPosition = ftell(File);
 149                                 break;
 150                         case SEEK_SET:
 151                                 mCurrentPosition = Offset;
 152                                 break;
 153                 }
 154         }
 155 }
 156
 157 size_t StdIOCallback::write(const void*Buffer,size_t Size)
 158 {
 159         assert(File!=0);
 160         uint32 Result = fwrite(Buffer,1,Size,File);
 161         mCurrentPosition += Result;
 162         return Result;
 163 }
 164
 165 uint64 StdIOCallback::getFilePointer()
 166 {
 167         assert(File!=0);
 168
 169 #if 0
 170         long Result=ftell(File);
 171         if(Result<0)
 172         {
 173 #if !defined(__GNUC__) || (__GNUC__ > 2)
 174                 stringstream Msg;
 175                 Msg<<"Can't tell the current file pointer position for "<<File;
 176                 throw CRTError(Msg.str());
 177 #endif // GCC2
 178         }
 179 #endif
 180
 181         return mCurrentPosition;
 182 }
 183
 184 void StdIOCallback::close()
 185 {
 186         if(File==0)
 187                 return;
 188
 189         if(fclose(File)!=0)
 190         {
 191 #if !defined(__GNUC__) || (__GNUC__ > 2)
 192                 stringstream Msg;
 193                 Msg<<"Can't close file "<<File;
 194                 throw CRTError(Msg.str());
 195 #endif // GCC2
 196         }
 197
 198         File=0;
 199 }
 200
 201 END_LIBEBML_NAMESPACE