1// (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com)
2// (C) Copyright 2004-2007 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#ifndef BOOST_IOSTREAMS_FILTER_STREAM_HPP_INCLUDED
9#define BOOST_IOSTREAMS_FILTER_STREAM_HPP_INCLUDED
10
11#if defined(_MSC_VER)
12# pragma once
13#endif
14
15#include <memory> // allocator.
16#include <boost/iostreams/detail/access_control.hpp>
17#include <boost/iostreams/detail/char_traits.hpp>
18#include <boost/iostreams/detail/iostream.hpp> // standard streams.
19#include <boost/iostreams/detail/push.hpp>
20#include <boost/iostreams/detail/select.hpp>
21#include <boost/iostreams/detail/streambuf.hpp> // pubsync.
22#include <boost/iostreams/filtering_streambuf.hpp>
23#include <boost/mpl/and.hpp>
24#include <boost/mpl/bool.hpp>
25#include <boost/static_assert.hpp>
26#include <boost/type_traits/is_convertible.hpp>
27
28// Must come last.
29#include <boost/iostreams/detail/config/disable_warnings.hpp> // MSVC.
30
31namespace boost { namespace iostreams {
32
33//--------------Definition of filtered_istream--------------------------------//
34
35namespace detail {
36
37template<typename Mode, typename Ch, typename Tr>
38struct filtering_stream_traits {
39 typedef typename
40 iostreams::select< // Disambiguation for Tru64
41 mpl::and_<
42 is_convertible<Mode, input>,
43 is_convertible<Mode, output>
44 >,
45 BOOST_IOSTREAMS_BASIC_IOSTREAM(Ch, Tr),
46 is_convertible<Mode, input>,
47 BOOST_IOSTREAMS_BASIC_ISTREAM(Ch, Tr),
48 else_,
49 BOOST_IOSTREAMS_BASIC_OSTREAM(Ch, Tr)
50 >::type stream_type;
51 typedef typename
52 iostreams::select< // Dismbiguation required for Tru64.
53 mpl::and_<
54 is_convertible<Mode, input>,
55 is_convertible<Mode, output>
56 >,
57 iostream_tag,
58 is_convertible<Mode, input>,
59 istream_tag,
60 else_,
61 ostream_tag
62 >::type stream_tag;
63};
64
65#if defined(BOOST_MSVC) && (BOOST_MSVC == 1700)
66# pragma warning(push)
67// https://connect.microsoft.com/VisualStudio/feedback/details/733720/
68# pragma warning(disable: 4250)
69#endif
70
71template<typename Chain, typename Access>
72class filtering_stream_base
73 : public access_control<
74 boost::iostreams::detail::chain_client<Chain>,
75 Access
76 >,
77 public filtering_stream_traits<
78 typename Chain::mode,
79 typename Chain::char_type,
80 typename Chain::traits_type
81 >::stream_type
82{
83public:
84 typedef Chain chain_type;
85 typedef access_control<
86 boost::iostreams::detail::chain_client<Chain>,
87 Access
88 > client_type;
89protected:
90 typedef typename
91 filtering_stream_traits<
92 typename Chain::mode,
93 typename Chain::char_type,
94 typename Chain::traits_type
95 >::stream_type stream_type;
96 filtering_stream_base() : stream_type(0) { this->set_chain(&chain_); }
97private:
98 void notify() { this->rdbuf(chain_.empty() ? 0 : &chain_.front()); }
99 Chain chain_;
100};
101
102#if defined(BOOST_MSVC) && (BOOST_MSVC == 1700)
103# pragma warning(pop)
104#endif
105
106} // End namespace detail.
107
108//
109// Macro: BOOST_IOSTREAMS_DEFINE_FILTER_STREAM(name_, chain_type_, default_char_)
110// Description: Defines a template derived from std::basic_streambuf which uses
111// a chain to perform i/o. The template has the following parameters:
112// Mode - the i/o mode.
113// Ch - The character type.
114// Tr - The character traits type.
115// Alloc - The allocator type.
116// Access - Indicates accessibility of the chain interface; must be either
117// public_ or protected_; defaults to public_.
118// Macro parameters:
119// name_ - The name of the template to be defined.
120// chain_type_ - The name of the chain template.
121// default_char_ - The default value for the char template parameter.
122//
123#define BOOST_IOSTREAMS_DEFINE_FILTER_STREAM(name_, chain_type_, default_char_) \
124 template< typename Mode, \
125 typename Ch = default_char_, \
126 typename Tr = BOOST_IOSTREAMS_CHAR_TRAITS(Ch), \
127 typename Alloc = std::allocator<Ch>, \
128 typename Access = public_ > \
129 class name_ \
130 : public boost::iostreams::detail::filtering_stream_base< \
131 chain_type_<Mode, Ch, Tr, Alloc>, Access \
132 > \
133 { \
134 public: \
135 typedef Ch char_type; \
136 struct category \
137 : Mode, \
138 closable_tag, \
139 detail::filtering_stream_traits<Mode, Ch, Tr>::stream_tag \
140 { }; \
141 BOOST_IOSTREAMS_STREAMBUF_TYPEDEFS(Tr) \
142 typedef Mode mode; \
143 typedef chain_type_<Mode, Ch, Tr, Alloc> chain_type; \
144 name_() { } \
145 BOOST_IOSTREAMS_DEFINE_PUSH_CONSTRUCTOR(name_, mode, Ch, push_impl) \
146 ~name_() { \
147 if (this->is_complete()) \
148 this->rdbuf()->BOOST_IOSTREAMS_PUBSYNC(); \
149 } \
150 private: \
151 typedef access_control< \
152 boost::iostreams::detail::chain_client< \
153 chain_type_<Mode, Ch, Tr, Alloc> \
154 >, \
155 Access \
156 > client_type; \
157 template<typename T> \
158 void push_impl(const T& t BOOST_IOSTREAMS_PUSH_PARAMS()) \
159 { client_type::push(t BOOST_IOSTREAMS_PUSH_ARGS()); } \
160 }; \
161 /**/
162
163#if defined(BOOST_MSVC) && (BOOST_MSVC == 1700)
164# pragma warning(push)
165// https://connect.microsoft.com/VisualStudio/feedback/details/733720/
166# pragma warning(disable: 4250)
167#endif
168
169BOOST_IOSTREAMS_DEFINE_FILTER_STREAM(filtering_stream, boost::iostreams::chain, char)
170BOOST_IOSTREAMS_DEFINE_FILTER_STREAM(wfiltering_stream, boost::iostreams::chain, wchar_t)
171
172#if defined(BOOST_MSVC) && (BOOST_MSVC == 1700)
173# pragma warning(pop)
174#endif
175
176typedef filtering_stream<input> filtering_istream;
177typedef filtering_stream<output> filtering_ostream;
178typedef wfiltering_stream<input> filtering_wistream;
179typedef wfiltering_stream<output> filtering_wostream;
180
181//----------------------------------------------------------------------------//
182
183} } // End namespace iostreams, boost
184
185#include <boost/iostreams/detail/config/enable_warnings.hpp> // MSVC
186
187#endif // #ifndef BOOST_IOSTREAMS_FILTER_STREAM_HPP_INCLUDED
188

source code of boost/libs/iostreams/include/boost/iostreams/filtering_stream.hpp