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diff --git a/src/io/base64.hh b/src/io/base64.hh
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+/*  This file is part of the OpenLB library
+ *
+ *  Copyright (C) 2007 Jonas Latt
+ *  E-mail contact: info@openlb.net
+ *  The most recent release of OpenLB can be downloaded at
+ *  <http://www.openlb.net/>
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version 2
+ *  of the License, or (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public
+ *  License along with this program; if not, write to the Free
+ *  Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ *  Boston, MA  02110-1301, USA.
+*/
+
+/* Acknowledgment: The strategy adopted here to encode
+ * and decode Base64, and in particular the expression of the
+ * arrays Base64Encoder::enc64 and Base64Decoder::dec64,
+ * is inspired by the open source library b64 by Bob Trower,
+ * which is distributed with a MIT license at the address
+ * http://base64.sourceforge.net/b64.c
+ */
+
+#ifndef BASE64_HH
+#define BASE64_HH
+
+#include "base64.h"
+#include "core/olbDebug.h"
+#include <ostream>
+#include <istream>
+
+
+namespace olb {
+
+////////////// class Base64Encoder ////////////////////////////////////////////
+
+template<typename T>
+const char Base64Encoder<T>::enc64[65]=
+  "ABCDEFGHIJKLMNOPQRSTUVWXYZ" \
+  "abcdefghijklmnopqrstuvwxyz0123456789+/";
+
+template<typename T>
+Base64Encoder<T>::Base64Encoder(std::ostream& ostr_, size_t fullLength_)
+  : ostr(ostr_),
+    charFullLength(fullLength_ * sizeof(T)),
+    numWritten(0),
+    numOverflow(0)
+{ }
+
+template<typename T>
+void Base64Encoder<T>::encode(const T* data, size_t length)
+{
+  const unsigned char* charData = reinterpret_cast<const unsigned char*>(data);
+  size_t charLength = length * sizeof(T);
+  OLB_PRECONDITION( numWritten+charLength <= charFullLength );
+
+  size_t pos=0;
+  fillOverflow(charData, charLength, pos);
+  while (pos+3 <= charLength) {
+    encodeBlock(charData+pos);
+    pos += 3;
+  }
+  fillOverflow(charData, charLength, pos);
+  numWritten += charLength;
+  if (numWritten == charFullLength) {
+    flushOverflow();
+  }
+}
+
+template<typename T>
+void Base64Encoder<T>::fillOverflow(const unsigned char* charData, size_t charLength, size_t& pos)
+{
+  while (numOverflow < 3 && pos < charLength) {
+    overflow[numOverflow] = charData[pos];
+    ++numOverflow;
+    ++pos;
+  }
+  if (numOverflow == 3) {
+    encodeBlock(overflow);
+    numOverflow = 0;
+  }
+}
+
+template<typename T>
+void Base64Encoder<T>::flushOverflow()
+{
+  if (numOverflow > 0) {
+    for (int iOverflow = numOverflow; iOverflow<3; ++iOverflow) {
+      overflow[iOverflow] = 0;
+    }
+    encodeUnfinishedBlock(overflow, numOverflow);
+    numOverflow = 0;
+  }
+}
+
+template<typename T>
+void Base64Encoder<T>::encodeBlock( const unsigned char* data)
+{
+  ostr << enc64[ data[0] >> 2 ];
+  ostr << enc64[ ((data[0] & 0x03) << 4) | ((data[1] & 0xf0) >> 4) ];
+  ostr << (unsigned char) (enc64[ ((data[1] & 0x0f) << 2) | ((data[2] & 0xc0) >> 6) ]);
+  ostr << (unsigned char) (enc64[ data[2] & 0x3f ]);
+}
+
+template<typename T>
+void Base64Encoder<T>::encodeUnfinishedBlock( const unsigned char* data, int length )
+{
+  ostr << enc64[ data[0] >> 2 ];
+  ostr << enc64[ ((data[0] & 0x03) << 4) | ((data[1] & 0xf0) >> 4) ];
+  ostr << (unsigned char) (
+         length == 2 ?
+         enc64[ ((data[1] & 0x0f) << 2) | ((data[2] & 0xc0) >> 6) ] :
+         '='
+       );
+  ostr << (unsigned char) ( '=' );
+}
+
+
+////////////// struct Base64Decoder ////////////////////////////////////////////
+
+template<typename T>
+const char Base64Decoder<T>::dec64[82]=
+  "|###}rstuvwxyz{#######>?@"\
+  "ABCDEFGHIJKLMNOPQRSTUVW######XYZ"\
+  "[\\]^_`abcdefghijklmnopq";
+
+
+template<typename T>
+Base64Decoder<T>::Base64Decoder(std::istream& istr_, size_t fullLength_)
+  : istr(istr_),
+    charFullLength(fullLength_ * sizeof(T)),
+    numRead(0),
+    posOverflow(3)
+{ }
+
+template<typename T>
+void Base64Decoder<T>::decode(T* data, size_t length)
+{
+  unsigned char* charData = reinterpret_cast<unsigned char*>(data);
+  size_t charLength = length * sizeof(T);
+  OLB_PRECONDITION( numRead+charLength <= charFullLength );
+
+  size_t pos = 0;
+  flushOverflow(charData, charLength, pos);
+  while (pos+3 <= charLength) {
+    decodeBlock(charData+pos);
+    pos += 3;
+  }
+  if (pos < charLength) {
+    decodeBlock(overflow);
+    posOverflow=0;
+    flushOverflow(charData, charLength, pos);
+  }
+  numRead += charLength;
+}
+
+template<typename T>
+void Base64Decoder<T>::flushOverflow(unsigned char* charData, size_t charLength, size_t& pos)
+{
+  while (posOverflow < 3 && pos < charLength) {
+    charData[pos] = overflow[posOverflow];
+    ++pos;
+    ++posOverflow;
+  }
+}
+
+template<typename T>
+unsigned char Base64Decoder<T>::getNext()
+{
+  unsigned char nextChar;
+  istr >> nextChar;
+  return (unsigned char) (dec64[nextChar - 43] - 62);
+}
+
+template<typename T>
+void Base64Decoder<T>::decodeBlock(unsigned char* data)
+{
+  unsigned char input[4];
+  input[0] = getNext();
+  input[1] = getNext();
+  input[2] = getNext();
+  input[3] = getNext();
+  data[0] = (unsigned char) (input[0] << 2 | input[1] >> 4);
+  data[1] = (unsigned char) (input[1] << 4 | input[2] >> 2);
+  data[2] = (unsigned char) (((input[2] << 6) & 0xc0) | input[3]);
+}
+
+}  // namespace olb
+
+#endif
+
+