ceph/src/boost/libs/spirit/include/boost/spirit/home/karma/binary/padding.hpp

   1 //  Copyright (c) 2001-2011 Hartmut Kaiser
   2 //
   3 //  Distributed under the Boost Software License, Version 1.0. (See accompanying
   4 //  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   5
   6 #if !defined(BOOST_SPIRIT_KARMA_PADDING_MAY_06_2008_0436PM)
   7 #define BOOST_SPIRIT_KARMA_PADDING_MAY_06_2008_0436PM
   8
   9 #if defined(_MSC_VER)
  10 #pragma once
  11 #endif
  12
  13 #include <boost/spirit/home/support/common_terminals.hpp>
  14 #include <boost/spirit/home/support/info.hpp>
  15
  16 #include <boost/spirit/home/karma/domain.hpp>
  17 #include <boost/spirit/home/karma/meta_compiler.hpp>
  18 #include <boost/spirit/home/karma/delimit_out.hpp>
  19 #include <boost/spirit/home/karma/auxiliary/lazy.hpp>
  20 #include <boost/spirit/home/karma/detail/generate_to.hpp>
  21 #include <boost/spirit/home/support/unused.hpp>
  22 #include <boost/fusion/include/at.hpp>
  23 #include <boost/fusion/include/vector.hpp>
  24
  25 ///////////////////////////////////////////////////////////////////////////////
  26 namespace boost { namespace spirit
  27 {
  28     ///////////////////////////////////////////////////////////////////////////
  29     // Enablers
  30     ///////////////////////////////////////////////////////////////////////////
  31
  32     // enables pad(...)
  33     template <typename A0>
  34     struct use_terminal<karma::domain
  35         , terminal_ex<tag::pad, fusion::vector1<A0> > >
  36       : mpl::true_ {};
  37
  38     // enables lazy pad(...)
  39     template <>
  40     struct use_lazy_terminal<karma::domain, tag::pad, 1>
  41       : mpl::true_ {};
  42
  43 }}
  44
  45 ///////////////////////////////////////////////////////////////////////////////
  46 namespace boost { namespace spirit { namespace karma
  47 {
  48 #ifndef BOOST_SPIRIT_NO_PREDEFINED_TERMINALS
  49     using boost::spirit::pad;
  50 #endif
  51     using boost::spirit::pad_type;
  52
  53     struct binary_padding_generator
  54       : primitive_generator<binary_padding_generator>
  55     {
  56         typedef mpl::int_<generator_properties::tracking> properties;
  57
  58         template <typename Context, typename Unused>
  59         struct attribute
  60         {
  61             typedef unused_type type;
  62         };
  63
  64         binary_padding_generator(int numpadbytes)
  65           : numpadbytes_(numpadbytes)
  66         {}
  67
  68         template <
  69             typename OutputIterator, typename Context, typename Delimiter
  70           , typename Attribute>
  71         bool generate(OutputIterator& sink, Context&, Delimiter const& d
  72           , Attribute const& /*attr*/) const
  73         {
  74             std::size_t count = sink.get_out_count() % numpadbytes_;
  75             if (count)
  76                 count = numpadbytes_ - count;
  77
  78             bool result = true;
  79             while (result && count-- != 0)
  80                 result = detail::generate_to(sink, '\0');
  81
  82             if (result)
  83                 result = karma::delimit_out(sink, d);  // always do post-delimiting
  84             return result;
  85         }
  86
  87         template <typename Context>
  88         static info what(Context const&)
  89         {
  90             return info("pad");
  91         }
  92
  93         int numpadbytes_;
  94     };
  95
  96     ///////////////////////////////////////////////////////////////////////////
  97     // Generator generators: make_xxx function (objects)
  98     ///////////////////////////////////////////////////////////////////////////
  99     template <typename Modifiers, typename A0>
 100     struct make_primitive<
 101         terminal_ex<tag::pad, fusion::vector1<A0> >
 102       , Modifiers>
 103     {
 104         typedef binary_padding_generator result_type;
 105
 106         template <typename Terminal>
 107         result_type operator()(Terminal const& term, unused_type) const
 108         {
 109             return result_type(fusion::at_c<0>(term.args));
 110         }
 111     };
 112
 113 }}}
 114
 115 #endif