categories.hpp source code [boost/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) && (_MSC_VER >= 1020)
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
176

source code of boost/boost/iostreams/categories.hpp