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 + result, n - result); 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 // write errors, like EOF on read, need to be handled. 45 if (amt == -1) 46 break; 47 result += amt; 48 } 49 return result; 50 } seek(stream_offset off,BOOST_IOS::seekdir way,BOOST_IOS::openmode which=BOOST_IOS::in|BOOST_IOS::out)51 std::streampos seek( stream_offset off, BOOST_IOS::seekdir way, 52 BOOST_IOS::openmode which = 53 BOOST_IOS::in | BOOST_IOS::out ) 54 { return iostreams::seek(device_, off, way, which); } 55 public: 56 non_blocking_adapter& operator=(const non_blocking_adapter&); 57 Device& device_; 58 }; 59 60 } } // End namespace iostreams. 61 62 #endif // #ifndef BOOST_IOSTREAMS_DETAIL_NON_BLOCKING_ADAPTER_HPP_INCLUDED 63