232 lines
6.6 KiB
C++
232 lines
6.6 KiB
C++
/*
|
|
|
|
Copyright (c) 2007-2016, Arvid Norberg
|
|
All rights reserved.
|
|
|
|
Redistribution and use in source and binary forms, with or without
|
|
modification, are permitted provided that the following conditions
|
|
are met:
|
|
|
|
* Redistributions of source code must retain the above copyright
|
|
notice, this list of conditions and the following disclaimer.
|
|
* Redistributions in binary form must reproduce the above copyright
|
|
notice, this list of conditions and the following disclaimer in
|
|
the documentation and/or other materials provided with the distribution.
|
|
* Neither the name of the author nor the names of its
|
|
contributors may be used to endorse or promote products derived
|
|
from this software without specific prior written permission.
|
|
|
|
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
|
|
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
POSSIBILITY OF SUCH DAMAGE.
|
|
|
|
*/
|
|
|
|
#ifndef TORRENT_CHAINED_BUFFER_HPP_INCLUDED
|
|
#define TORRENT_CHAINED_BUFFER_HPP_INCLUDED
|
|
|
|
#include "libtorrent/config.hpp"
|
|
#include "libtorrent/aux_/block_cache_reference.hpp"
|
|
#include "libtorrent/debug.hpp"
|
|
#include "libtorrent/buffer.hpp"
|
|
|
|
#include <deque>
|
|
#include <vector>
|
|
|
|
#include "libtorrent/aux_/disable_warnings_push.hpp"
|
|
#include <boost/asio/buffer.hpp>
|
|
#include "libtorrent/aux_/disable_warnings_pop.hpp"
|
|
|
|
#ifdef _MSC_VER
|
|
// visual studio requires the value in a deque to be copyable. C++11
|
|
// has looser requirements depending on which functions are actually used.
|
|
#define TORRENT_CPP98_DEQUE 1
|
|
#else
|
|
#define TORRENT_CPP98_DEQUE 0
|
|
#endif
|
|
|
|
namespace libtorrent
|
|
{
|
|
// TODO: 2 this type should probably be renamed to send_buffer
|
|
struct TORRENT_EXTRA_EXPORT chained_buffer : private single_threaded
|
|
{
|
|
chained_buffer(): m_bytes(0), m_capacity(0)
|
|
{
|
|
thread_started();
|
|
#if TORRENT_USE_ASSERTS
|
|
m_destructed = false;
|
|
#endif
|
|
}
|
|
|
|
private:
|
|
|
|
// destructs/frees the holder object
|
|
using destruct_holder_fun = void (*)(void*);
|
|
using move_construct_holder_fun = void (*)(void*, void*);
|
|
|
|
struct buffer_t
|
|
{
|
|
buffer_t() {}
|
|
#if TORRENT_CPP98_DEQUE
|
|
buffer_t(buffer_t&& rhs) noexcept
|
|
{
|
|
destruct_holder = rhs.destruct_holder;
|
|
move_holder = rhs.move_holder;
|
|
buf = rhs.buf;
|
|
size = rhs.size;
|
|
used_size = rhs.used_size;
|
|
move_holder(&holder, &rhs.holder);
|
|
}
|
|
buffer_t& operator=(buffer_t&& rhs) noexcept
|
|
{
|
|
destruct_holder(&holder);
|
|
destruct_holder = rhs.destruct_holder;
|
|
move_holder = rhs.move_holder;
|
|
buf = rhs.buf;
|
|
size = rhs.size;
|
|
used_size = rhs.used_size;
|
|
move_holder(&holder, &rhs.holder);
|
|
return *this;
|
|
}
|
|
buffer_t(buffer_t const& rhs) noexcept
|
|
: buffer_t(std::move(const_cast<buffer_t&>(rhs))) {}
|
|
buffer_t& operator=(buffer_t const& rhs) noexcept
|
|
{ return this->operator=(std::move(const_cast<buffer_t&>(rhs))); }
|
|
#else
|
|
buffer_t(buffer_t&&) = delete;
|
|
buffer_t& operator=(buffer_t&&) = delete;
|
|
buffer_t(buffer_t const&) = delete;
|
|
buffer_t& operator=(buffer_t const&) = delete;
|
|
#endif
|
|
|
|
destruct_holder_fun destruct_holder;
|
|
#if TORRENT_CPP98_DEQUE
|
|
move_construct_holder_fun move_holder;
|
|
#endif
|
|
std::aligned_storage<24>::type holder;
|
|
char* buf; // the first byte of the buffer
|
|
int size; // the total size of the buffer
|
|
int used_size; // this is the number of bytes to send/receive
|
|
};
|
|
|
|
public:
|
|
|
|
bool empty() const { return m_bytes == 0; }
|
|
int size() const { return m_bytes; }
|
|
int capacity() const { return m_capacity; }
|
|
|
|
void pop_front(int bytes_to_pop);
|
|
|
|
template <typename Holder>
|
|
void append_buffer(Holder buffer, int s, int used_size)
|
|
{
|
|
TORRENT_ASSERT(is_single_thread());
|
|
TORRENT_ASSERT(s >= used_size);
|
|
m_vec.emplace_back();
|
|
buffer_t& b = m_vec.back();
|
|
init_buffer_entry<Holder>(b, buffer, s, used_size);
|
|
}
|
|
|
|
template <typename Holder>
|
|
void prepend_buffer(Holder buffer, int s, int used_size)
|
|
{
|
|
TORRENT_ASSERT(is_single_thread());
|
|
TORRENT_ASSERT(s >= used_size);
|
|
m_vec.emplace_front();
|
|
buffer_t& b = m_vec.front();
|
|
init_buffer_entry<Holder>(b, buffer, s, used_size);
|
|
}
|
|
|
|
// returns the number of bytes available at the
|
|
// end of the last chained buffer.
|
|
int space_in_last_buffer();
|
|
|
|
// tries to copy the given buffer to the end of the
|
|
// last chained buffer. If there's not enough room
|
|
// it returns nullptr
|
|
char* append(char const* buf, int s);
|
|
|
|
// tries to allocate memory from the end
|
|
// of the last buffer. If there isn't
|
|
// enough room, returns 0
|
|
char* allocate_appendix(int s);
|
|
|
|
std::vector<boost::asio::const_buffer> const& build_iovec(int to_send);
|
|
|
|
void clear();
|
|
|
|
void build_mutable_iovec(int bytes, std::vector<span<char>>& vec);
|
|
|
|
~chained_buffer();
|
|
|
|
private:
|
|
|
|
template <typename Holder>
|
|
void init_buffer_entry(buffer_t& b, Holder& buffer, int s, int used_size)
|
|
{
|
|
static_assert(sizeof(Holder) <= sizeof(b.holder), "buffer holder too large");
|
|
|
|
b.buf = buffer.get();
|
|
b.size = s;
|
|
b.used_size = used_size;
|
|
|
|
#ifdef _MSC_VER
|
|
// this appears to be a false positive msvc warning
|
|
#pragma warning(push, 1)
|
|
#pragma warning(disable : 4100)
|
|
#endif
|
|
b.destruct_holder = [](void* holder)
|
|
{ reinterpret_cast<Holder*>(holder)->~Holder(); };
|
|
|
|
#if TORRENT_CPP98_DEQUE
|
|
b.move_holder = [](void* dst, void* src)
|
|
{ new (dst) Holder(std::move(*reinterpret_cast<Holder*>(src))); };
|
|
#endif
|
|
|
|
#ifdef _MSC_VER
|
|
#pragma warning(pop)
|
|
#endif
|
|
|
|
new (&b.holder) Holder(std::move(buffer));
|
|
|
|
m_bytes += used_size;
|
|
m_capacity += s;
|
|
TORRENT_ASSERT(m_bytes <= m_capacity);
|
|
}
|
|
|
|
template <typename Buffer>
|
|
void build_vec(int bytes, std::vector<Buffer>& vec);
|
|
|
|
// this is the list of all the buffers we want to
|
|
// send
|
|
std::deque<buffer_t> m_vec;
|
|
|
|
// this is the number of bytes in the send buf.
|
|
// this will always be equal to the sum of the
|
|
// size of all buffers in vec
|
|
int m_bytes;
|
|
|
|
// the total size of all buffers in the chain
|
|
// including unused space
|
|
int m_capacity;
|
|
|
|
// this is the vector of buffers used when
|
|
// invoking the async write call
|
|
std::vector<boost::asio::const_buffer> m_tmp_vec;
|
|
|
|
#if TORRENT_USE_ASSERTS
|
|
bool m_destructed;
|
|
#endif
|
|
};
|
|
}
|
|
|
|
#endif
|