1 // (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com)
2 // (C) Copyright 2005-2007 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_DETAIL_NON_BLOCKING_ADAPTER_HPP_INCLUDED
9 #define BOOST_IOSTREAMS_DETAIL_NON_BLOCKING_ADAPTER_HPP_INCLUDED
10 
11 #include <boost/iostreams/detail/ios.hpp>  // streamsize, seekdir, openmode.
12 #include <boost/iostreams/read.hpp>
13 #include <boost/iostreams/seek.hpp>
14 #include <boost/iostreams/traits.hpp>
15 #include <boost/iostreams/write.hpp>
16 
17 namespace boost { namespace iostreams {
18 
19 template<typename Device>
20 class non_blocking_adapter {
21 public:
22     typedef typename char_type_of<Device>::type char_type;
23     struct category
24         : mode_of<Device>::type, device_tag
25         { };
non_blocking_adapter(Device & dev)26     explicit non_blocking_adapter(Device& dev) : device_(dev) { }
read(char_type * s,std::streamsize n)27     std::streamsize read(char_type* s, std::streamsize n)
28     {
29         std::streamsize result = 0;
30         while (result < n) {
31             std::streamsize amt = iostreams::read(device_, s, n);
32             if (amt == -1)
33                 break;
34             result += amt;
35         }
36         return result != 0 ? result : -1;
37     }
write(const char_type * s,std::streamsize n)38     std::streamsize write(const char_type* s, std::streamsize n)
39     {
40         std::streamsize result = 0;
41         while (result < n) {
42             std::streamsize amt =
43                 iostreams::write(device_, s + result, n - result);
44             result += amt;
45         }
46         return result;
47     }
seek(stream_offset off,BOOST_IOS::seekdir way,BOOST_IOS::openmode which=BOOST_IOS::in|BOOST_IOS::out)48     std::streampos seek( stream_offset off, BOOST_IOS::seekdir way,
49                          BOOST_IOS::openmode which =
50                              BOOST_IOS::in | BOOST_IOS::out )
51     { return iostreams::seek(device_, off, way, which); }
52 public:
53     non_blocking_adapter& operator=(const non_blocking_adapter&);
54     Device& device_;
55 };
56 
57 } } // End namespace iostreams.
58 
59 #endif // #ifndef BOOST_IOSTREAMS_DETAIL_NON_BLOCKING_ADAPTER_HPP_INCLUDED
60