// (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com) | |
// (C) Copyright 2003-2007 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. | |
// Contains: The function template copy, which reads data from a Source | |
// and writes it to a Sink until the end of the sequence is reached, returning | |
// the number of characters transfered. | |
// The implementation is complicated by the need to handle smart adapters | |
// and direct devices. | |
#ifndef BOOST_IOSTREAMS_COPY_HPP_INCLUDED | |
#define BOOST_IOSTREAMS_COPY_HPP_INCLUDED | |
#if defined(_MSC_VER) && (_MSC_VER >= 1020) | |
# pragma once | |
#endif | |
#include <boost/config.hpp> // Make sure ptrdiff_t is in std. | |
#include <algorithm> // copy, min. | |
#include <cstddef> // ptrdiff_t. | |
#include <utility> // pair. | |
#include <boost/bind.hpp> | |
#include <boost/detail/workaround.hpp> | |
#include <boost/iostreams/chain.hpp> | |
#include <boost/iostreams/constants.hpp> | |
#include <boost/iostreams/detail/adapter/non_blocking_adapter.hpp> | |
#include <boost/iostreams/detail/buffer.hpp> | |
#include <boost/iostreams/detail/enable_if_stream.hpp> | |
#include <boost/iostreams/detail/execute.hpp> | |
#include <boost/iostreams/detail/functional.hpp> | |
#include <boost/iostreams/detail/ios.hpp> // failure, streamsize. | |
#include <boost/iostreams/detail/resolve.hpp> | |
#include <boost/iostreams/detail/wrap_unwrap.hpp> | |
#include <boost/iostreams/operations.hpp> // read, write, close. | |
#include <boost/iostreams/pipeline.hpp> | |
#include <boost/static_assert.hpp> | |
#include <boost/type_traits/is_same.hpp> | |
namespace boost { namespace iostreams { | |
namespace detail { | |
// The following four overloads of copy_impl() optimize | |
// copying in the case that one or both of the two devices | |
// models Direct (see | |
// http://www.boost.org/libs/iostreams/doc/index.html?path=4.1.1.4) | |
// Copy from a direct source to a direct sink | |
template<typename Source, typename Sink> | |
std::streamsize copy_impl( Source& src, Sink& snk, | |
std::streamsize /* buffer_size */, | |
mpl::true_, mpl::true_ ) | |
{ | |
using namespace std; | |
typedef typename char_type_of<Source>::type char_type; | |
typedef std::pair<char_type*, char_type*> pair_type; | |
pair_type p1 = iostreams::input_sequence(src); | |
pair_type p2 = iostreams::output_sequence(snk); | |
std::streamsize total = | |
static_cast<std::streamsize>( | |
(std::min)(p1.second - p1.first, p2.second - p2.first) | |
); | |
std::copy(p1.first, p1.first + total, p2.first); | |
return total; | |
} | |
// Copy from a direct source to an indirect sink | |
template<typename Source, typename Sink> | |
std::streamsize copy_impl( Source& src, Sink& snk, | |
std::streamsize /* buffer_size */, | |
mpl::true_, mpl::false_ ) | |
{ | |
using namespace std; | |
typedef typename char_type_of<Source>::type char_type; | |
typedef std::pair<char_type*, char_type*> pair_type; | |
pair_type p = iostreams::input_sequence(src); | |
std::streamsize size, total; | |
for ( total = 0, size = static_cast<std::streamsize>(p.second - p.first); | |
total < size; ) | |
{ | |
std::streamsize amt = | |
iostreams::write(snk, p.first + total, size - total); | |
total += amt; | |
} | |
return total; | |
} | |
// Copy from an indirect source to a direct sink | |
template<typename Source, typename Sink> | |
std::streamsize copy_impl( Source& src, Sink& snk, | |
std::streamsize buffer_size, | |
mpl::false_, mpl::true_ ) | |
{ | |
typedef typename char_type_of<Source>::type char_type; | |
typedef std::pair<char_type*, char_type*> pair_type; | |
detail::basic_buffer<char_type> buf(buffer_size); | |
pair_type p = snk.output_sequence(); | |
std::streamsize total = 0; | |
std::ptrdiff_t capacity = p.second - p.first; | |
while (true) { | |
std::streamsize amt = | |
iostreams::read( | |
src, | |
buf.data(), | |
buffer_size < capacity - total ? | |
buffer_size : | |
static_cast<std::streamsize>(capacity - total) | |
); | |
if (amt == -1) | |
break; | |
std::copy(buf.data(), buf.data() + amt, p.first + total); | |
total += amt; | |
} | |
return total; | |
} | |
// Copy from an indirect source to an indirect sink | |
template<typename Source, typename Sink> | |
std::streamsize copy_impl( Source& src, Sink& snk, | |
std::streamsize buffer_size, | |
mpl::false_, mpl::false_ ) | |
{ | |
typedef typename char_type_of<Source>::type char_type; | |
detail::basic_buffer<char_type> buf(buffer_size); | |
non_blocking_adapter<Sink> nb(snk); | |
std::streamsize total = 0; | |
bool done = false; | |
while (!done) { | |
std::streamsize amt; | |
done = (amt = iostreams::read(src, buf.data(), buffer_size)) == -1; | |
if (amt != -1) { | |
iostreams::write(nb, buf.data(), amt); | |
total += amt; | |
} | |
} | |
return total; | |
} | |
// The following function object is used with | |
// boost::iostreams::detail::execute() in the primary | |
// overload of copy_impl(), below | |
// Function object that delegates to one of the above four | |
// overloads of compl_impl() | |
template<typename Source, typename Sink> | |
class copy_operation { | |
public: | |
typedef std::streamsize result_type; | |
copy_operation(Source& src, Sink& snk, std::streamsize buffer_size) | |
: src_(src), snk_(snk), buffer_size_(buffer_size) | |
{ } | |
std::streamsize operator()() | |
{ | |
return copy_impl( src_, snk_, buffer_size_, | |
is_direct<Source>(), is_direct<Sink>() ); | |
} | |
private: | |
copy_operation& operator=(const copy_operation&); | |
Source& src_; | |
Sink& snk_; | |
std::streamsize buffer_size_; | |
}; | |
// Primary overload of copy_impl. Delegates to one of the above four | |
// overloads of compl_impl(), depending on which of the two given | |
// devices, if any, models Direct (see | |
// http://www.boost.org/libs/iostreams/doc/index.html?path=4.1.1.4) | |
template<typename Source, typename Sink> | |
std::streamsize copy_impl(Source src, Sink snk, std::streamsize buffer_size) | |
{ | |
using namespace std; | |
typedef typename char_type_of<Source>::type src_char; | |
typedef typename char_type_of<Sink>::type snk_char; | |
BOOST_STATIC_ASSERT((is_same<src_char, snk_char>::value)); | |
return detail::execute_all( | |
copy_operation<Source, Sink>(src, snk, buffer_size), | |
detail::call_close_all(src), | |
detail::call_close_all(snk) | |
); | |
} | |
} // End namespace detail. | |
//------------------Definition of copy----------------------------------------// | |
// Overload of copy() for the case where neither the source nor the sink is | |
// a standard stream or stream buffer | |
template<typename Source, typename Sink> | |
std::streamsize | |
copy( const Source& src, const Sink& snk, | |
std::streamsize buffer_size = default_device_buffer_size | |
BOOST_IOSTREAMS_DISABLE_IF_STREAM(Source) | |
BOOST_IOSTREAMS_DISABLE_IF_STREAM(Sink) ) | |
{ | |
typedef typename char_type_of<Source>::type char_type; | |
return detail::copy_impl( detail::resolve<input, char_type>(src), | |
detail::resolve<output, char_type>(snk), | |
buffer_size ); | |
} | |
#if !BOOST_WORKAROUND(BOOST_MSVC, <= 1300) //---------------------------------// | |
// Overload of copy() for the case where the source, but not the sink, is | |
// a standard stream or stream buffer | |
template<typename Source, typename Sink> | |
std::streamsize | |
copy( Source& src, const Sink& snk, | |
std::streamsize buffer_size = default_device_buffer_size | |
BOOST_IOSTREAMS_ENABLE_IF_STREAM(Source) | |
BOOST_IOSTREAMS_DISABLE_IF_STREAM(Sink) ) | |
{ | |
typedef typename char_type_of<Source>::type char_type; | |
return detail::copy_impl( detail::wrap(src), | |
detail::resolve<output, char_type>(snk), | |
buffer_size ); | |
} | |
// Overload of copy() for the case where the sink, but not the source, is | |
// a standard stream or stream buffer | |
template<typename Source, typename Sink> | |
std::streamsize | |
copy( const Source& src, Sink& snk, | |
std::streamsize buffer_size = default_device_buffer_size | |
BOOST_IOSTREAMS_DISABLE_IF_STREAM(Source) | |
BOOST_IOSTREAMS_ENABLE_IF_STREAM(Sink) ) | |
{ | |
typedef typename char_type_of<Source>::type char_type; | |
return detail::copy_impl( detail::resolve<input, char_type>(src), | |
detail::wrap(snk), buffer_size ); | |
} | |
// Overload of copy() for the case where neither the source nor the sink is | |
// a standard stream or stream buffer | |
template<typename Source, typename Sink> | |
std::streamsize | |
copy( Source& src, Sink& snk, | |
std::streamsize buffer_size = default_device_buffer_size | |
BOOST_IOSTREAMS_ENABLE_IF_STREAM(Source) | |
BOOST_IOSTREAMS_ENABLE_IF_STREAM(Sink) ) | |
{ | |
return detail::copy_impl(detail::wrap(src), detail::wrap(snk), buffer_size); | |
} | |
#endif // #if !BOOST_WORKAROUND(BOOST_MSVC, <= 1300) //-----------------------// | |
} } // End namespaces iostreams, boost. | |
#endif // #ifndef BOOST_IOSTREAMS_COPY_HPP_INCLUDED |