| // (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com) |
| // (C) Copyright 2005-2007 Jonathan Turkanis |
| // Distributed under the Boost Software License, Version 1.0. (See accompanying |
| // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt.) |
| |
| // See http://www.boost.org/libs/iostreams for documentation. |
| |
| #ifndef BOOST_IOSTREAMS_EXAMPLE_CONTAINTER_DEVICE_HPP_INCLUDED |
| #define BOOST_IOSTREAMS_EXAMPLE_CONTAINTER_DEVICE_HPP_INCLUDED |
| |
| #include <algorithm> // copy, min. |
| #include <cassert> |
| #include <boost/config.hpp> // BOOST_NO_STDC_NAMESPACE. |
| #include <boost/iostreams/categories.hpp> |
| #include <boost/iostreams/detail/ios.hpp> // failure. |
| |
| namespace boost { namespace iostreams { namespace example { |
| |
| // |
| // Model of Source which reads from an STL-compatible sequence |
| // whose iterators are random-access iterators. |
| // |
| template<typename Container> |
| class container_source { |
| public: |
| typedef typename Container::value_type char_type; |
| typedef source_tag category; |
| container_source(Container& container) |
| : container_(container), pos_(0) |
| { } |
| std::streamsize read(char_type* s, std::streamsize n) |
| { |
| using namespace std; |
| std::streamsize amt = |
| static_cast<std::streamsize>(container_.size() - pos_); |
| std::streamsize result = (min)(n, amt); |
| if (result != 0) { |
| std::copy( container_.begin() + pos_, |
| container_.begin() + pos_ + result, |
| s ); |
| pos_ += result; |
| return result; |
| } else { |
| return -1; // EOF |
| } |
| } |
| Container& container() { return container_; } |
| private: |
| container_source operator=(const container_source&); |
| typedef typename Container::size_type size_type; |
| Container& container_; |
| size_type pos_; |
| }; |
| |
| // |
| // Model of Sink which appends to an STL-compatible sequence. |
| // |
| template<typename Container> |
| class container_sink { |
| public: |
| typedef typename Container::value_type char_type; |
| typedef sink_tag category; |
| container_sink(Container& container) : container_(container) { } |
| std::streamsize write(const char_type* s, std::streamsize n) |
| { |
| container_.insert(container_.end(), s, s + n); |
| return n; |
| } |
| Container& container() { return container_; } |
| private: |
| container_sink operator=(const container_sink&); |
| Container& container_; |
| }; |
| |
| // |
| // Model of SeekableDevice which accessS an TL-compatible sequence |
| // whose iterators are random-access iterators. |
| // |
| template<typename Container> |
| class container_device { |
| public: |
| typedef typename Container::value_type char_type; |
| typedef seekable_device_tag category; |
| container_device(Container& container) |
| : container_(container), pos_(0) |
| { } |
| |
| std::streamsize read(char_type* s, std::streamsize n) |
| { |
| using namespace std; |
| std::streamsize amt = |
| static_cast<std::streamsize>(container_.size() - pos_); |
| std::streamsize result = (min)(n, amt); |
| if (result != 0) { |
| std::copy( container_.begin() + pos_, |
| container_.begin() + pos_ + result, |
| s ); |
| pos_ += result; |
| return result; |
| } else { |
| return -1; // EOF |
| } |
| } |
| std::streamsize write(const char_type* s, std::streamsize n) |
| { |
| using namespace std; |
| std::streamsize result = 0; |
| if (pos_ != container_.size()) { |
| std::streamsize amt = |
| static_cast<std::streamsize>(container_.size() - pos_); |
| result = (min)(n, amt); |
| std::copy(s, s + result, container_.begin() + pos_); |
| pos_ += result; |
| } |
| if (result < n) { |
| container_.insert(container_.end(), s, s + n); |
| pos_ = container_.size(); |
| } |
| return n; |
| } |
| stream_offset seek(stream_offset off, BOOST_IOS::seekdir way) |
| { |
| using namespace std; |
| |
| // Determine new value of pos_ |
| stream_offset next; |
| if (way == BOOST_IOS::beg) { |
| next = off; |
| } else if (way == BOOST_IOS::cur) { |
| next = pos_ + off; |
| } else if (way == BOOST_IOS::end) { |
| next = container_.size() + off - 1; |
| } else { |
| throw BOOST_IOSTREAMS_FAILURE("bad seek direction"); |
| } |
| |
| // Check for errors |
| if (next < 0 || next >= container_.size()) |
| throw BOOST_IOSTREAMS_FAILURE("bad seek offset"); |
| |
| pos_ = next; |
| return pos_; |
| } |
| |
| Container& container() { return container_; } |
| private: |
| container_device operator=(const container_device&); |
| typedef typename Container::size_type size_type; |
| Container& container_; |
| size_type pos_; |
| }; |
| |
| } } } // End namespaces example, iostreams, boost. |
| |
| #endif // #ifndef BOOST_IOSTREAMS_EXAMPLE_CONTAINTER_DEVICE_HPP_INCLUDED |