Ugly, not-to-be-pushed sucking in of all of Boost to get windows to work.
[dyninst.git] / external / boost / iostreams / device / null.hpp
1 // (C) Copyright Jonathan Turkanis 2004.
2 // Distributed under the Boost Software License, Version 1.0. (See accompanying
3 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt.)
4
5 // See http://www.boost.org/libs/iostreams for documentation.
6
7 // Inspired by Daryle Walker's nullbuf from his More I/O submission.
8
9 #ifndef BOOST_IOSTREAMS_NULL_HPP_INCLUDED
10 #define BOOST_IOSTREAMS_NULL_HPP_INCLUDED
11
12 #if defined(_MSC_VER) && (_MSC_VER >= 1020)
13 # pragma once
14 #endif
15
16 #include <boost/iostreams/categories.hpp>
17 #include <boost/iostreams/detail/ios.hpp> // openmode, streamsize.
18 #include <boost/iostreams/positioning.hpp>
19
20 namespace boost { namespace iostreams {
21
22 template<typename Ch, typename Mode>
23 class basic_null_device {
24 public:
25     typedef Ch char_type;
26     struct category
27         : public Mode,
28           public device_tag,
29           public closable_tag
30         { };
31     std::streamsize read(Ch*, std::streamsize) { return 0; }
32     std::streamsize write(const Ch*, std::streamsize n) { return n; }
33     std::streampos seek( stream_offset, BOOST_IOS::seekdir,
34                          BOOST_IOS::openmode = 
35                              BOOST_IOS::in | BOOST_IOS::out ) 
36     { return -1; }
37     void close(BOOST_IOS::openmode = BOOST_IOS::in | BOOST_IOS::out) { }
38 };
39
40 template<typename Ch>
41 struct basic_null_source : private basic_null_device<Ch, input> {
42     typedef Ch          char_type;
43     typedef source_tag  category;
44     using basic_null_device<Ch, input>::read;
45     using basic_null_device<Ch, input>::close;
46 };
47
48 typedef basic_null_source<char>     null_source;
49 typedef basic_null_source<wchar_t>  wnull_source;
50
51 template<typename Ch>
52 struct basic_null_sink : private basic_null_device<Ch, output> {
53     typedef Ch        char_type;
54     typedef sink_tag  category;
55     using basic_null_device<Ch, output>::write;
56     using basic_null_device<Ch, output>::close;
57 };
58
59 typedef basic_null_sink<char>     null_sink;
60 typedef basic_null_sink<wchar_t>  wnull_sink;
61
62 } } // End namespaces iostreams, boost.
63
64 #endif // #ifndef BOOST_IOSTREAMS_NULL_HPP_INCLUDED