ceph/src/boost/boost/archive/iterators/binary_from_base64.hpp

   1 #ifndef BOOST_ARCHIVE_ITERATORS_BINARY_FROM_BASE64_HPP
   2 #define BOOST_ARCHIVE_ITERATORS_BINARY_FROM_BASE64_HPP
   3
   4 // MS compatible compilers support #pragma once
   5 #if defined(_MSC_VER)
   6 # pragma once
   7 #endif
   8
   9 /////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
  10 // binary_from_base64.hpp
  11
  12 // (C) Copyright 2002 Robert Ramey - http://www.rrsd.com .
  13 // Use, modification and distribution is subject to the Boost Software
  14 // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
  15 // http://www.boost.org/LICENSE_1_0.txt)
  16
  17 //  See http://www.boost.org for updates, documentation, and revision history.
  18
  19 #include <boost/assert.hpp>
  20
  21 #include <boost/serialization/throw_exception.hpp>
  22 #include <boost/static_assert.hpp>
  23
  24 #include <boost/iterator/transform_iterator.hpp>
  25 #include <boost/archive/iterators/dataflow_exception.hpp>
  26
  27 namespace boost {
  28 namespace archive {
  29 namespace iterators {
  30
  31 /////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
  32 // convert base64 characters to binary data
  33
  34 namespace detail {
  35
  36 template<class CharType>
  37 struct to_6_bit {
  38     typedef CharType result_type;
  39     CharType operator()(CharType t) const{
  40         static const signed char lookup_table[] = {
  41             -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
  42             -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
  43             -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,62,-1,-1,-1,63,
  44             52,53,54,55,56,57,58,59,60,61,-1,-1,-1, 0,-1,-1, // render '=' as 0
  45             -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,
  46             15,16,17,18,19,20,21,22,23,24,25,-1,-1,-1,-1,-1,
  47             -1,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,
  48             41,42,43,44,45,46,47,48,49,50,51,-1,-1,-1,-1,-1
  49         };
  50         // metrowerks trips this assertion - how come?
  51         #if ! defined(__MWERKS__)
  52         BOOST_STATIC_ASSERT(128 == sizeof(lookup_table));
  53         #endif
  54         signed char value = -1;
  55         if((unsigned)t <= 127)
  56             value = lookup_table[(unsigned)t];
  57         if(-1 == value)
  58             boost::serialization::throw_exception(
  59                 dataflow_exception(dataflow_exception::invalid_base64_character)
  60             );
  61         return value;
  62     }
  63 };
  64
  65 } // namespace detail
  66
  67 // note: what we would like to do is
  68 // template<class Base, class CharType = typename Base::value_type>
  69 //  typedef transform_iterator<
  70 //      from_6_bit<CharType>,
  71 //      transform_width<Base, 6, sizeof(Base::value_type) * 8, CharType>
  72 //  > base64_from_binary;
  73 // but C++ won't accept this.  Rather than using a "type generator" and
  74 // using a different syntax, make a derivation which should be equivalent.
  75 //
  76 // Another issue addressed here is that the transform_iterator doesn't have
  77 // a templated constructor.  This makes it incompatible with the dataflow
  78 // ideal.  This is also addressed here.
  79
  80 template<
  81     class Base,
  82     class CharType = typename boost::iterator_value<Base>::type
  83 >
  84 class binary_from_base64 : public
  85     transform_iterator<
  86         detail::to_6_bit<CharType>,
  87         Base
  88     >
  89 {
  90     friend class boost::iterator_core_access;
  91     typedef transform_iterator<
  92         detail::to_6_bit<CharType>,
  93         Base
  94     > super_t;
  95 public:
  96     // make composible buy using templated constructor
  97     template<class T>
  98     binary_from_base64(T  start) :
  99         super_t(
 100             Base(static_cast< T >(start)),
 101             detail::to_6_bit<CharType>()
 102         )
 103     {}
 104     // intel 7.1 doesn't like default copy constructor
 105     binary_from_base64(const binary_from_base64 & rhs) :
 106         super_t(
 107             Base(rhs.base_reference()),
 108             detail::to_6_bit<CharType>()
 109         )
 110     {}
 111 //    binary_from_base64(){};
 112 };
 113
 114 } // namespace iterators
 115 } // namespace archive
 116 } // namespace boost
 117
 118 #endif // BOOST_ARCHIVE_ITERATORS_BINARY_FROM_BASE64_HPP