ceph/src/boost/libs/iostreams/include/boost/iostreams/categories.hpp

   1 // (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com)
   2 // (C) Copyright 2003-2007 Jonathan Turkanis
   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 // See http://www.boost.org/libs/iostreams for documentation.
   7
   8 // Contains category and mode tags for classifying filters, devices and
   9 // standard stream and stream buffers types.
  10
  11 #ifndef BOOST_IOSTREAMS_CATEGORIES_HPP_INCLUDED
  12 #define BOOST_IOSTREAMS_CATEGORIES_HPP_INCLUDED
  13
  14 #if defined(_MSC_VER)
  15 # pragma once
  16 #endif
  17
  18 namespace boost { namespace iostreams {
  19
  20 //------------------Tags for dispatch according to i/o mode-------------------//
  21
  22 struct any_tag { };
  23 namespace detail { struct two_sequence : virtual any_tag { }; }
  24 namespace detail { struct random_access : virtual any_tag { }; }
  25 namespace detail { struct one_head : virtual any_tag { }; }
  26 namespace detail { struct two_head : virtual any_tag { }; }
  27 struct input : virtual any_tag { };
  28 struct output : virtual any_tag { };
  29 struct bidirectional : virtual input, virtual output, detail::two_sequence { };
  30 struct dual_use : virtual input, virtual output { }; // Pseudo-mode.
  31 struct input_seekable : virtual input, virtual detail::random_access { };
  32 struct output_seekable : virtual output, virtual detail::random_access { };
  33 struct seekable
  34     : virtual input_seekable,
  35       virtual output_seekable,
  36       detail::one_head
  37     { };
  38 struct dual_seekable
  39     : virtual input_seekable,
  40       virtual output_seekable,
  41       detail::two_head
  42     { };
  43 struct bidirectional_seekable
  44     : input_seekable, output_seekable,
  45       bidirectional, detail::two_head
  46     { };
  47
  48 //------------------Tags for use as i/o categories----------------------------//
  49
  50 struct device_tag : virtual any_tag { };
  51 struct filter_tag : virtual any_tag { };
  52
  53     //
  54     // Tags for optional behavior.
  55     //
  56
  57 struct peekable_tag : virtual any_tag { };        // Devices.
  58 struct closable_tag : virtual any_tag { };
  59 struct flushable_tag : virtual any_tag { };
  60 struct localizable_tag : virtual any_tag { };
  61 struct optimally_buffered_tag : virtual any_tag { };
  62 struct direct_tag : virtual any_tag { };          // Devices.
  63 struct multichar_tag : virtual any_tag { };       // Filters.
  64
  65 struct source_tag : device_tag, input { };
  66 struct sink_tag : device_tag, output { };
  67 struct bidirectional_device_tag : device_tag, bidirectional { };
  68 struct seekable_device_tag : virtual device_tag, seekable { };
  69
  70 struct input_filter_tag : filter_tag, input { };
  71 struct output_filter_tag : filter_tag, output { };
  72 struct bidirectional_filter_tag : filter_tag, bidirectional { };
  73 struct seekable_filter_tag : filter_tag, seekable { };
  74 struct dual_use_filter_tag : filter_tag, dual_use { };
  75
  76 struct multichar_input_filter_tag
  77     : multichar_tag,
  78       input_filter_tag
  79     { };
  80 struct multichar_output_filter_tag
  81     : multichar_tag,
  82       output_filter_tag
  83     { };
  84 struct multichar_bidirectional_filter_tag
  85     : multichar_tag,
  86       bidirectional_filter_tag
  87     { };
  88 struct multichar_seekable_filter_tag
  89     : multichar_tag,
  90       seekable_filter_tag
  91     { };
  92 struct multichar_dual_use_filter_tag
  93     : multichar_tag,
  94       dual_use_filter_tag
  95     { };
  96
  97     //
  98     // Tags for standard streams and streambufs.
  99     //
 100
 101 struct std_io_tag : virtual localizable_tag { };
 102 struct istream_tag
 103     : virtual device_tag,
 104       virtual peekable_tag,
 105       virtual std_io_tag
 106     { };
 107 struct ostream_tag
 108     : virtual device_tag,
 109       virtual std_io_tag
 110     { };
 111 struct iostream_tag
 112     : istream_tag,
 113       ostream_tag
 114     { };
 115 struct streambuf_tag
 116     : device_tag,
 117       peekable_tag,
 118       std_io_tag
 119     { };
 120 struct ifstream_tag
 121     : input_seekable,
 122       closable_tag,
 123       istream_tag
 124     { };
 125 struct ofstream_tag
 126     : output_seekable,
 127       closable_tag,
 128       ostream_tag
 129     { };
 130 struct fstream_tag
 131     : seekable,
 132       closable_tag,
 133       iostream_tag
 134     { };
 135 struct filebuf_tag
 136     : seekable,
 137       closable_tag,
 138       streambuf_tag
 139     { };
 140 struct istringstream_tag
 141     : input_seekable,
 142       istream_tag
 143     { };
 144 struct ostringstream_tag
 145     : output_seekable,
 146       ostream_tag
 147     { };
 148 struct stringstream_tag
 149     : dual_seekable,
 150       iostream_tag
 151     { };
 152 struct stringbuf_tag
 153     : dual_seekable,
 154       streambuf_tag
 155     { };
 156 struct generic_istream_tag
 157     : input_seekable,
 158       istream_tag
 159     { };
 160 struct generic_ostream_tag
 161     : output_seekable,
 162       ostream_tag
 163     { };
 164 struct generic_iostream_tag
 165     : seekable,
 166       iostream_tag
 167     { };
 168 struct generic_streambuf_tag
 169     : seekable,
 170       streambuf_tag
 171     { };
 172
 173 } } // End namespaces iostreams, boost.
 174
 175 #endif // #ifndef BOOST_IOSTREAMS_CATEGORIES_HPP_INCLUDED