1// (C) Copyright Gennadiy Rozental 2001.
2// (C) Copyright Daryle Walker 2000-2001.
3// Distributed under the Boost Software License, Version 1.0.
4// (See accompanying file LICENSE_1_0.txt or copy at
5// http://www.boost.org/LICENSE_1_0.txt)
6
7// See http://www.boost.org/libs/test for the library home page.
8//
9// File : $RCSfile$
10//
11// Version : $Revision$
12//
13// Description : simulate /dev/null stream
14// ***************************************************************************
15
16#ifndef BOOST_TEST_UTILS_NULLSTREAM_HPP
17#define BOOST_TEST_UTILS_NULLSTREAM_HPP
18
19// STL
20#include <ostream> // for std::basic_ostream
21#include <streambuf> // for std::basic_streambuf
22#include <string> // for std::char_traits
23
24// Boost
25#include <boost/utility/base_from_member.hpp>
26
27#include <boost/test/detail/suppress_warnings.hpp>
28
29//____________________________________________________________________________//
30
31namespace boost {
32
33// ************************************************************************** //
34// ************** basic_nullbuf ************** //
35// ************************************************************************** //
36// Class for a buffer that reads nothing and writes to nothing.
37// Idea from an Usenet post by Tom <the_wid@my-deja.com> at
38// 27 Oct 2000 14:06:21 GMT on comp.lang.c++.
39
40template<typename CharType, class CharTraits = ::std::char_traits<CharType> >
41class basic_nullbuf : public ::std::basic_streambuf<CharType, CharTraits> {
42 typedef ::std::basic_streambuf<CharType, CharTraits> base_type;
43public:
44 // Types
45 typedef typename base_type::char_type char_type;
46 typedef typename base_type::traits_type traits_type;
47 typedef typename base_type::int_type int_type;
48 typedef typename base_type::pos_type pos_type;
49 typedef typename base_type::off_type off_type;
50
51 // Use automatic default constructor and destructor
52
53protected:
54 // The default implementations of the miscellaneous virtual
55 // member functions are sufficient.
56
57 // The default implementations of the input & putback virtual
58 // member functions, being nowhere but EOF, are sufficient.
59
60 // The output virtual member functions need to be changed to
61 // accept anything without any problems, instead of being at EOF.
62 virtual ::std::streamsize xsputn( char_type const* /*s*/, ::std::streamsize n ) { return n; } // "s" is unused
63 virtual int_type overflow( int_type c = traits_type::eof() ) { return traits_type::not_eof( c ); }
64};
65
66typedef basic_nullbuf<char> nullbuf;
67typedef basic_nullbuf<wchar_t> wnullbuf;
68
69// ************************************************************************** //
70// ************** basic_onullstream ************** //
71// ************************************************************************** //
72// Output streams based on basic_nullbuf.
73
74#ifdef BOOST_MSVC
75# pragma warning(push)
76# pragma warning(disable: 4355) // 'this' : used in base member initializer list
77#endif
78
79template< typename CharType, class CharTraits = ::std::char_traits<CharType> >
80class basic_onullstream : private boost::base_from_member<basic_nullbuf<CharType, CharTraits> >
81 , public ::std::basic_ostream<CharType, CharTraits> {
82 typedef boost::base_from_member<basic_nullbuf<CharType, CharTraits> > pbase_type;
83 typedef ::std::basic_ostream<CharType, CharTraits> base_type;
84public:
85 // Constructor
86 basic_onullstream() : pbase_type(), base_type( &this->pbase_type::member ) {}
87};
88
89#ifdef BOOST_MSVC
90# pragma warning(default: 4355)
91# pragma warning(pop)
92#endif
93
94typedef basic_onullstream<char> onullstream;
95typedef basic_onullstream<wchar_t> wonullstream;
96
97} // namespace boost
98
99//____________________________________________________________________________//
100
101#include <boost/test/detail/enable_warnings.hpp>
102
103#endif // BOOST_TEST_UTILS_NULLSTREAM_HPP
104