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

   1 /****************************************************************************
   2 ** libebml : parse EBML files, see http://embl.sourceforge.net/
   3 **
   4 ** <file/class description>
   5 **
   6 ** Copyright (C) 2002-2005 Steve Lhomme.  All rights reserved.
   7 **
   8 ** This file is part of libebml.
   9 **
  10 ** This library is free software; you can redistribute it and/or
  11 ** modify it under the terms of the GNU Lesser General Public
  12 ** License as published by the Free Software Foundation; either
  13 ** version 2.1 of the License, or (at your option) any later version.
  14 **
  15 ** This library is distributed in the hope that it will be useful,
  16 ** but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18 ** Lesser General Public License for more details.
  19 **
  20 ** You should have received a copy of the GNU Lesser General Public
  21 ** License along with this library; if not, write to the Free Software
  22 ** Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  23 **
  24 ** See http://www.matroska.org/license/lgpl/ for LGPL licensing information.
  25 **
  26 ** Contact license@matroska.org if any conditions of this licensing are
  27 ** not clear to you.
  28 **
  29 **********************************************************************/
  30
  31 /*!
  32         \file
  33         \version \$Id: EbmlFloat.cpp 1243 2006-03-30 19:33:22Z mosu $
  34         \author Steve Lhomme     <robux4 @ users.sf.net>
  35 */
  36
  37 #include <cassert>
  38
  39 #include "ebml/EbmlFloat.h"
  40
  41 START_LIBEBML_NAMESPACE
  42
  43 EbmlFloat::EbmlFloat(const EbmlFloat::Precision prec)
  44  :EbmlElement(0, false)
  45 {
  46         SetPrecision(prec);
  47 }
  48
  49 EbmlFloat::EbmlFloat(const double aDefaultValue, const EbmlFloat::Precision prec)
  50  :EbmlElement(0, true), Value(aDefaultValue), DefaultValue(aDefaultValue)
  51 {
  52         DefaultIsSet = true;
  53         SetPrecision(prec);
  54 }
  55
  56 EbmlFloat::EbmlFloat(const EbmlFloat & ElementToClone)
  57  :EbmlElement(ElementToClone)
  58  ,Value(ElementToClone.Value)
  59  ,DefaultValue(ElementToClone.DefaultValue)
  60 {
  61 }
  62
  63 /*!
  64         \todo handle exception on errors
  65         \todo handle 10 bits precision
  66 */
  67 uint32 EbmlFloat::RenderData(IOCallback & output, bool bForceRender, bool bKeepIntact)
  68 {
  69         assert(Size == 4 || Size == 8);
  70
  71         if (Size == 4) {
  72                 float val = Value;
  73                 int Tmp;
  74                 memcpy(&Tmp, &val, 4);
  75                 big_int32 TmpToWrite(Tmp);
  76                 output.writeFully(&TmpToWrite.endian(), Size);
  77         } else if (Size == 8) {
  78                 double val = Value;
  79                 int64 Tmp;
  80                 memcpy(&Tmp, &val, 8);
  81                 big_int64 TmpToWrite(Tmp);
  82                 output.writeFully(&TmpToWrite.endian(), Size);
  83         }
  84
  85         return Size;
  86 }
  87
  88 uint64 EbmlFloat::UpdateSize(bool bKeepIntact, bool bForceRender)
  89 {
  90         if (!bKeepIntact && IsDefaultValue())
  91                 return 0;
  92         return Size;
  93 }
  94
  95 /*!
  96         \todo remove the hack for possible endianess pb (test on little & big endian)
  97 */
  98 uint64 EbmlFloat::ReadData(IOCallback & input, ScopeMode ReadFully)
  99 {
 100         if (ReadFully != SCOPE_NO_DATA)
 101         {
 102                 binary Buffer[20];
 103                 assert(Size <= 20);
 104                 input.readFully(Buffer, Size);
 105
 106                 if (Size == 4) {
 107                         big_int32 TmpRead;
 108                         TmpRead.Eval(Buffer);
 109                         int32 tmpp = int32(TmpRead);
 110                         float val;
 111                         memcpy(&val, &tmpp, 4);
 112                         Value = val;
 113                         bValueIsSet = true;
 114                 } else if (Size == 8) {
 115                         big_int64 TmpRead;
 116                         TmpRead.Eval(Buffer);
 117                         int64 tmpp = int64(TmpRead);
 118                         double val;
 119                         memcpy(&val, &tmpp, 8);
 120                         Value = val;
 121                         bValueIsSet = true;
 122                 }
 123         }
 124
 125         return Size;
 126 }
 127
 128 END_LIBEBML_NAMESPACE