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// (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.
// Must come last.
#include <boost/iostreams/detail/config/disable_warnings.hpp>
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 > static_cast<stream_offset>(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.
#include <boost/iostreams/detail/config/enable_warnings.hpp>
#endif // #ifndef BOOST_IOSTREAMS_EXAMPLE_CONTAINTER_DEVICE_HPP_INCLUDED
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