775 lines
28 KiB
C++
775 lines
28 KiB
C++
//
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// impl/read_at.hpp
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// ~~~~~~~~~~~~~~~~
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//
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// Copyright (c) 2003-2023 Christopher M. Kohlhoff (chris at kohlhoff dot com)
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//
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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//
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#ifndef ASIO_IMPL_READ_AT_HPP
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#define ASIO_IMPL_READ_AT_HPP
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#if defined(_MSC_VER) && (_MSC_VER >= 1200)
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# pragma once
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#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
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#include <algorithm>
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#include "asio/associator.hpp"
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#include "asio/buffer.hpp"
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#include "asio/detail/array_fwd.hpp"
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#include "asio/detail/base_from_cancellation_state.hpp"
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#include "asio/detail/base_from_completion_cond.hpp"
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#include "asio/detail/bind_handler.hpp"
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#include "asio/detail/consuming_buffers.hpp"
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#include "asio/detail/dependent_type.hpp"
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#include "asio/detail/handler_alloc_helpers.hpp"
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#include "asio/detail/handler_cont_helpers.hpp"
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#include "asio/detail/handler_invoke_helpers.hpp"
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#include "asio/detail/handler_tracking.hpp"
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#include "asio/detail/handler_type_requirements.hpp"
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#include "asio/detail/non_const_lvalue.hpp"
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#include "asio/detail/throw_error.hpp"
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#include "asio/error.hpp"
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#include "asio/detail/push_options.hpp"
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namespace asio {
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namespace detail
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{
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template <typename SyncRandomAccessReadDevice, typename MutableBufferSequence,
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typename MutableBufferIterator, typename CompletionCondition>
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std::size_t read_at_buffer_sequence(SyncRandomAccessReadDevice& d,
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uint64_t offset, const MutableBufferSequence& buffers,
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const MutableBufferIterator&, CompletionCondition completion_condition,
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asio::error_code& ec)
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{
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ec = asio::error_code();
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asio::detail::consuming_buffers<mutable_buffer,
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MutableBufferSequence, MutableBufferIterator> tmp(buffers);
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while (!tmp.empty())
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{
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if (std::size_t max_size = detail::adapt_completion_condition_result(
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completion_condition(ec, tmp.total_consumed())))
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{
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tmp.consume(d.read_some_at(offset + tmp.total_consumed(),
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tmp.prepare(max_size), ec));
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}
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else
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break;
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}
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return tmp.total_consumed();
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}
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} // namespace detail
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template <typename SyncRandomAccessReadDevice, typename MutableBufferSequence,
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typename CompletionCondition>
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std::size_t read_at(SyncRandomAccessReadDevice& d,
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uint64_t offset, const MutableBufferSequence& buffers,
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CompletionCondition completion_condition, asio::error_code& ec)
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{
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return detail::read_at_buffer_sequence(d, offset, buffers,
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asio::buffer_sequence_begin(buffers),
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ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
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}
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template <typename SyncRandomAccessReadDevice, typename MutableBufferSequence>
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inline std::size_t read_at(SyncRandomAccessReadDevice& d,
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uint64_t offset, const MutableBufferSequence& buffers)
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{
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asio::error_code ec;
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std::size_t bytes_transferred = read_at(
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d, offset, buffers, transfer_all(), ec);
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asio::detail::throw_error(ec, "read_at");
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return bytes_transferred;
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}
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template <typename SyncRandomAccessReadDevice, typename MutableBufferSequence>
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inline std::size_t read_at(SyncRandomAccessReadDevice& d,
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uint64_t offset, const MutableBufferSequence& buffers,
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asio::error_code& ec)
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{
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return read_at(d, offset, buffers, transfer_all(), ec);
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}
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template <typename SyncRandomAccessReadDevice, typename MutableBufferSequence,
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typename CompletionCondition>
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inline std::size_t read_at(SyncRandomAccessReadDevice& d,
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uint64_t offset, const MutableBufferSequence& buffers,
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CompletionCondition completion_condition)
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{
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asio::error_code ec;
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std::size_t bytes_transferred = read_at(d, offset, buffers,
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ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
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asio::detail::throw_error(ec, "read_at");
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return bytes_transferred;
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}
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#if !defined(ASIO_NO_EXTENSIONS)
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#if !defined(ASIO_NO_IOSTREAM)
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template <typename SyncRandomAccessReadDevice, typename Allocator,
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typename CompletionCondition>
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std::size_t read_at(SyncRandomAccessReadDevice& d,
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uint64_t offset, asio::basic_streambuf<Allocator>& b,
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CompletionCondition completion_condition, asio::error_code& ec)
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{
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ec = asio::error_code();
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std::size_t total_transferred = 0;
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std::size_t max_size = detail::adapt_completion_condition_result(
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completion_condition(ec, total_transferred));
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std::size_t bytes_available = read_size_helper(b, max_size);
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while (bytes_available > 0)
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{
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std::size_t bytes_transferred = d.read_some_at(
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offset + total_transferred, b.prepare(bytes_available), ec);
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b.commit(bytes_transferred);
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total_transferred += bytes_transferred;
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max_size = detail::adapt_completion_condition_result(
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completion_condition(ec, total_transferred));
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bytes_available = read_size_helper(b, max_size);
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}
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return total_transferred;
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}
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template <typename SyncRandomAccessReadDevice, typename Allocator>
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inline std::size_t read_at(SyncRandomAccessReadDevice& d,
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uint64_t offset, asio::basic_streambuf<Allocator>& b)
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{
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asio::error_code ec;
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std::size_t bytes_transferred = read_at(
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d, offset, b, transfer_all(), ec);
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asio::detail::throw_error(ec, "read_at");
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return bytes_transferred;
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}
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template <typename SyncRandomAccessReadDevice, typename Allocator>
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inline std::size_t read_at(SyncRandomAccessReadDevice& d,
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uint64_t offset, asio::basic_streambuf<Allocator>& b,
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asio::error_code& ec)
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{
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return read_at(d, offset, b, transfer_all(), ec);
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}
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template <typename SyncRandomAccessReadDevice, typename Allocator,
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typename CompletionCondition>
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inline std::size_t read_at(SyncRandomAccessReadDevice& d,
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uint64_t offset, asio::basic_streambuf<Allocator>& b,
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CompletionCondition completion_condition)
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{
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asio::error_code ec;
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std::size_t bytes_transferred = read_at(d, offset, b,
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ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
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asio::detail::throw_error(ec, "read_at");
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return bytes_transferred;
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}
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#endif // !defined(ASIO_NO_IOSTREAM)
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#endif // !defined(ASIO_NO_EXTENSIONS)
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namespace detail
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{
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template <typename AsyncRandomAccessReadDevice,
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typename MutableBufferSequence, typename MutableBufferIterator,
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typename CompletionCondition, typename ReadHandler>
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class read_at_op
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: public base_from_cancellation_state<ReadHandler>,
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base_from_completion_cond<CompletionCondition>
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{
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public:
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read_at_op(AsyncRandomAccessReadDevice& device,
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uint64_t offset, const MutableBufferSequence& buffers,
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CompletionCondition& completion_condition, ReadHandler& handler)
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: base_from_cancellation_state<ReadHandler>(
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handler, enable_partial_cancellation()),
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base_from_completion_cond<CompletionCondition>(completion_condition),
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device_(device),
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offset_(offset),
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buffers_(buffers),
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start_(0),
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handler_(ASIO_MOVE_CAST(ReadHandler)(handler))
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{
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}
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#if defined(ASIO_HAS_MOVE)
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read_at_op(const read_at_op& other)
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: base_from_cancellation_state<ReadHandler>(other),
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base_from_completion_cond<CompletionCondition>(other),
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device_(other.device_),
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offset_(other.offset_),
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buffers_(other.buffers_),
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start_(other.start_),
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handler_(other.handler_)
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{
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}
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read_at_op(read_at_op&& other)
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: base_from_cancellation_state<ReadHandler>(
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ASIO_MOVE_CAST(base_from_cancellation_state<
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ReadHandler>)(other)),
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base_from_completion_cond<CompletionCondition>(
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ASIO_MOVE_CAST(base_from_completion_cond<
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CompletionCondition>)(other)),
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device_(other.device_),
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offset_(other.offset_),
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buffers_(ASIO_MOVE_CAST(buffers_type)(other.buffers_)),
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start_(other.start_),
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handler_(ASIO_MOVE_CAST(ReadHandler)(other.handler_))
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{
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}
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#endif // defined(ASIO_HAS_MOVE)
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void operator()(asio::error_code ec,
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std::size_t bytes_transferred, int start = 0)
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{
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std::size_t max_size;
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switch (start_ = start)
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{
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case 1:
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max_size = this->check_for_completion(ec, buffers_.total_consumed());
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for (;;)
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{
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{
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ASIO_HANDLER_LOCATION((__FILE__, __LINE__, "async_read_at"));
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device_.async_read_some_at(
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offset_ + buffers_.total_consumed(), buffers_.prepare(max_size),
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ASIO_MOVE_CAST(read_at_op)(*this));
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}
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return; default:
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buffers_.consume(bytes_transferred);
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if ((!ec && bytes_transferred == 0) || buffers_.empty())
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break;
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max_size = this->check_for_completion(ec, buffers_.total_consumed());
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if (max_size == 0)
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break;
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if (this->cancelled() != cancellation_type::none)
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{
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ec = asio::error::operation_aborted;
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break;
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}
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}
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ASIO_MOVE_OR_LVALUE(ReadHandler)(handler_)(
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static_cast<const asio::error_code&>(ec),
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static_cast<const std::size_t&>(buffers_.total_consumed()));
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}
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}
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//private:
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typedef asio::detail::consuming_buffers<mutable_buffer,
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MutableBufferSequence, MutableBufferIterator> buffers_type;
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AsyncRandomAccessReadDevice& device_;
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uint64_t offset_;
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buffers_type buffers_;
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int start_;
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ReadHandler handler_;
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};
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template <typename AsyncRandomAccessReadDevice,
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typename MutableBufferSequence, typename MutableBufferIterator,
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typename CompletionCondition, typename ReadHandler>
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inline asio_handler_allocate_is_deprecated
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asio_handler_allocate(std::size_t size,
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read_at_op<AsyncRandomAccessReadDevice, MutableBufferSequence,
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MutableBufferIterator, CompletionCondition, ReadHandler>* this_handler)
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{
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#if defined(ASIO_NO_DEPRECATED)
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asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
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return asio_handler_allocate_is_no_longer_used();
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#else // defined(ASIO_NO_DEPRECATED)
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return asio_handler_alloc_helpers::allocate(
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size, this_handler->handler_);
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#endif // defined(ASIO_NO_DEPRECATED)
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}
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template <typename AsyncRandomAccessReadDevice,
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typename MutableBufferSequence, typename MutableBufferIterator,
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typename CompletionCondition, typename ReadHandler>
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inline asio_handler_deallocate_is_deprecated
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asio_handler_deallocate(void* pointer, std::size_t size,
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read_at_op<AsyncRandomAccessReadDevice, MutableBufferSequence,
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MutableBufferIterator, CompletionCondition, ReadHandler>* this_handler)
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{
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asio_handler_alloc_helpers::deallocate(
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pointer, size, this_handler->handler_);
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#if defined(ASIO_NO_DEPRECATED)
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return asio_handler_deallocate_is_no_longer_used();
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#endif // defined(ASIO_NO_DEPRECATED)
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}
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template <typename AsyncRandomAccessReadDevice,
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typename MutableBufferSequence, typename MutableBufferIterator,
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typename CompletionCondition, typename ReadHandler>
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inline bool asio_handler_is_continuation(
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read_at_op<AsyncRandomAccessReadDevice, MutableBufferSequence,
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MutableBufferIterator, CompletionCondition, ReadHandler>* this_handler)
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{
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return this_handler->start_ == 0 ? true
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: asio_handler_cont_helpers::is_continuation(
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this_handler->handler_);
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}
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template <typename Function, typename AsyncRandomAccessReadDevice,
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typename MutableBufferSequence, typename MutableBufferIterator,
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typename CompletionCondition, typename ReadHandler>
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inline asio_handler_invoke_is_deprecated
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asio_handler_invoke(Function& function,
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read_at_op<AsyncRandomAccessReadDevice, MutableBufferSequence,
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MutableBufferIterator, CompletionCondition, ReadHandler>* this_handler)
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{
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asio_handler_invoke_helpers::invoke(
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function, this_handler->handler_);
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#if defined(ASIO_NO_DEPRECATED)
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return asio_handler_invoke_is_no_longer_used();
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#endif // defined(ASIO_NO_DEPRECATED)
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}
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template <typename Function, typename AsyncRandomAccessReadDevice,
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typename MutableBufferSequence, typename MutableBufferIterator,
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typename CompletionCondition, typename ReadHandler>
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inline asio_handler_invoke_is_deprecated
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asio_handler_invoke(const Function& function,
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read_at_op<AsyncRandomAccessReadDevice, MutableBufferSequence,
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MutableBufferIterator, CompletionCondition, ReadHandler>* this_handler)
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{
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asio_handler_invoke_helpers::invoke(
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function, this_handler->handler_);
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#if defined(ASIO_NO_DEPRECATED)
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return asio_handler_invoke_is_no_longer_used();
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#endif // defined(ASIO_NO_DEPRECATED)
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}
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template <typename AsyncRandomAccessReadDevice,
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typename MutableBufferSequence, typename MutableBufferIterator,
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typename CompletionCondition, typename ReadHandler>
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inline void start_read_at_op(AsyncRandomAccessReadDevice& d,
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uint64_t offset, const MutableBufferSequence& buffers,
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const MutableBufferIterator&, CompletionCondition& completion_condition,
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ReadHandler& handler)
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{
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detail::read_at_op<AsyncRandomAccessReadDevice, MutableBufferSequence,
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MutableBufferIterator, CompletionCondition, ReadHandler>(
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d, offset, buffers, completion_condition, handler)(
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asio::error_code(), 0, 1);
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}
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template <typename AsyncRandomAccessReadDevice>
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class initiate_async_read_at
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{
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public:
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typedef typename AsyncRandomAccessReadDevice::executor_type executor_type;
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explicit initiate_async_read_at(AsyncRandomAccessReadDevice& device)
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: device_(device)
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{
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}
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executor_type get_executor() const ASIO_NOEXCEPT
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{
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return device_.get_executor();
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}
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template <typename ReadHandler, typename MutableBufferSequence,
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typename CompletionCondition>
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void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
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uint64_t offset, const MutableBufferSequence& buffers,
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ASIO_MOVE_ARG(CompletionCondition) completion_cond) const
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{
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// If you get an error on the following line it means that your handler
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// does not meet the documented type requirements for a ReadHandler.
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ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
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non_const_lvalue<ReadHandler> handler2(handler);
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non_const_lvalue<CompletionCondition> completion_cond2(completion_cond);
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start_read_at_op(device_, offset, buffers,
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asio::buffer_sequence_begin(buffers),
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completion_cond2.value, handler2.value);
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}
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private:
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AsyncRandomAccessReadDevice& device_;
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};
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} // namespace detail
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#if !defined(GENERATING_DOCUMENTATION)
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template <template <typename, typename> class Associator,
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typename AsyncRandomAccessReadDevice, typename MutableBufferSequence,
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typename MutableBufferIterator, typename CompletionCondition,
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typename ReadHandler, typename DefaultCandidate>
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struct associator<Associator,
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detail::read_at_op<AsyncRandomAccessReadDevice, MutableBufferSequence,
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MutableBufferIterator, CompletionCondition, ReadHandler>,
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DefaultCandidate>
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: Associator<ReadHandler, DefaultCandidate>
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{
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static typename Associator<ReadHandler, DefaultCandidate>::type
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get(const detail::read_at_op<AsyncRandomAccessReadDevice,
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MutableBufferSequence, MutableBufferIterator,
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CompletionCondition, ReadHandler>& h) ASIO_NOEXCEPT
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{
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return Associator<ReadHandler, DefaultCandidate>::get(h.handler_);
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}
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static ASIO_AUTO_RETURN_TYPE_PREFIX2(
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typename Associator<ReadHandler, DefaultCandidate>::type)
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get(const detail::read_at_op<AsyncRandomAccessReadDevice,
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MutableBufferSequence, MutableBufferIterator,
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CompletionCondition, ReadHandler>& h,
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const DefaultCandidate& c) ASIO_NOEXCEPT
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ASIO_AUTO_RETURN_TYPE_SUFFIX((
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Associator<ReadHandler, DefaultCandidate>::get(h.handler_, c)))
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{
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return Associator<ReadHandler, DefaultCandidate>::get(h.handler_, c);
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}
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};
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#endif // !defined(GENERATING_DOCUMENTATION)
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template <typename AsyncRandomAccessReadDevice,
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typename MutableBufferSequence, typename CompletionCondition,
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ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
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std::size_t)) ReadToken>
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inline ASIO_INITFN_AUTO_RESULT_TYPE_PREFIX(ReadToken,
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void (asio::error_code, std::size_t))
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async_read_at(AsyncRandomAccessReadDevice& d,
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uint64_t offset, const MutableBufferSequence& buffers,
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CompletionCondition completion_condition,
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ASIO_MOVE_ARG(ReadToken) token)
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ASIO_INITFN_AUTO_RESULT_TYPE_SUFFIX((
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async_initiate<ReadToken,
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void (asio::error_code, std::size_t)>(
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declval<detail::initiate_async_read_at<AsyncRandomAccessReadDevice> >(),
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token, offset, buffers,
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ASIO_MOVE_CAST(CompletionCondition)(completion_condition))))
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{
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return async_initiate<ReadToken,
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void (asio::error_code, std::size_t)>(
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detail::initiate_async_read_at<AsyncRandomAccessReadDevice>(d),
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token, offset, buffers,
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ASIO_MOVE_CAST(CompletionCondition)(completion_condition));
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}
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template <typename AsyncRandomAccessReadDevice, typename MutableBufferSequence,
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ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
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std::size_t)) ReadToken>
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inline ASIO_INITFN_AUTO_RESULT_TYPE_PREFIX(ReadToken,
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void (asio::error_code, std::size_t))
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async_read_at(AsyncRandomAccessReadDevice& d,
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uint64_t offset, const MutableBufferSequence& buffers,
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ASIO_MOVE_ARG(ReadToken) token)
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ASIO_INITFN_AUTO_RESULT_TYPE_SUFFIX((
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async_initiate<ReadToken,
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void (asio::error_code, std::size_t)>(
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declval<detail::initiate_async_read_at<AsyncRandomAccessReadDevice> >(),
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token, offset, buffers, transfer_all())))
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{
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return async_initiate<ReadToken,
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void (asio::error_code, std::size_t)>(
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|
detail::initiate_async_read_at<AsyncRandomAccessReadDevice>(d),
|
|
token, offset, buffers, transfer_all());
|
|
}
|
|
|
|
#if !defined(ASIO_NO_EXTENSIONS)
|
|
#if !defined(ASIO_NO_IOSTREAM)
|
|
|
|
namespace detail
|
|
{
|
|
template <typename AsyncRandomAccessReadDevice, typename Allocator,
|
|
typename CompletionCondition, typename ReadHandler>
|
|
class read_at_streambuf_op
|
|
: public base_from_cancellation_state<ReadHandler>,
|
|
base_from_completion_cond<CompletionCondition>
|
|
{
|
|
public:
|
|
read_at_streambuf_op(AsyncRandomAccessReadDevice& device,
|
|
uint64_t offset, basic_streambuf<Allocator>& streambuf,
|
|
CompletionCondition& completion_condition, ReadHandler& handler)
|
|
: base_from_cancellation_state<ReadHandler>(
|
|
handler, enable_partial_cancellation()),
|
|
base_from_completion_cond<CompletionCondition>(completion_condition),
|
|
device_(device),
|
|
offset_(offset),
|
|
streambuf_(streambuf),
|
|
start_(0),
|
|
total_transferred_(0),
|
|
handler_(ASIO_MOVE_CAST(ReadHandler)(handler))
|
|
{
|
|
}
|
|
|
|
#if defined(ASIO_HAS_MOVE)
|
|
read_at_streambuf_op(const read_at_streambuf_op& other)
|
|
: base_from_cancellation_state<ReadHandler>(other),
|
|
base_from_completion_cond<CompletionCondition>(other),
|
|
device_(other.device_),
|
|
offset_(other.offset_),
|
|
streambuf_(other.streambuf_),
|
|
start_(other.start_),
|
|
total_transferred_(other.total_transferred_),
|
|
handler_(other.handler_)
|
|
{
|
|
}
|
|
|
|
read_at_streambuf_op(read_at_streambuf_op&& other)
|
|
: base_from_cancellation_state<ReadHandler>(
|
|
ASIO_MOVE_CAST(base_from_cancellation_state<
|
|
ReadHandler>)(other)),
|
|
base_from_completion_cond<CompletionCondition>(
|
|
ASIO_MOVE_CAST(base_from_completion_cond<
|
|
CompletionCondition>)(other)),
|
|
device_(other.device_),
|
|
offset_(other.offset_),
|
|
streambuf_(other.streambuf_),
|
|
start_(other.start_),
|
|
total_transferred_(other.total_transferred_),
|
|
handler_(ASIO_MOVE_CAST(ReadHandler)(other.handler_))
|
|
{
|
|
}
|
|
#endif // defined(ASIO_HAS_MOVE)
|
|
|
|
void operator()(asio::error_code ec,
|
|
std::size_t bytes_transferred, int start = 0)
|
|
{
|
|
std::size_t max_size, bytes_available;
|
|
switch (start_ = start)
|
|
{
|
|
case 1:
|
|
max_size = this->check_for_completion(ec, total_transferred_);
|
|
bytes_available = read_size_helper(streambuf_, max_size);
|
|
for (;;)
|
|
{
|
|
{
|
|
ASIO_HANDLER_LOCATION((__FILE__, __LINE__, "async_read_at"));
|
|
device_.async_read_some_at(offset_ + total_transferred_,
|
|
streambuf_.prepare(bytes_available),
|
|
ASIO_MOVE_CAST(read_at_streambuf_op)(*this));
|
|
}
|
|
return; default:
|
|
total_transferred_ += bytes_transferred;
|
|
streambuf_.commit(bytes_transferred);
|
|
max_size = this->check_for_completion(ec, total_transferred_);
|
|
bytes_available = read_size_helper(streambuf_, max_size);
|
|
if ((!ec && bytes_transferred == 0) || bytes_available == 0)
|
|
break;
|
|
if (this->cancelled() != cancellation_type::none)
|
|
{
|
|
ec = asio::error::operation_aborted;
|
|
break;
|
|
}
|
|
}
|
|
|
|
ASIO_MOVE_OR_LVALUE(ReadHandler)(handler_)(
|
|
static_cast<const asio::error_code&>(ec),
|
|
static_cast<const std::size_t&>(total_transferred_));
|
|
}
|
|
}
|
|
|
|
//private:
|
|
AsyncRandomAccessReadDevice& device_;
|
|
uint64_t offset_;
|
|
asio::basic_streambuf<Allocator>& streambuf_;
|
|
int start_;
|
|
std::size_t total_transferred_;
|
|
ReadHandler handler_;
|
|
};
|
|
|
|
template <typename AsyncRandomAccessReadDevice, typename Allocator,
|
|
typename CompletionCondition, typename ReadHandler>
|
|
inline asio_handler_allocate_is_deprecated
|
|
asio_handler_allocate(std::size_t size,
|
|
read_at_streambuf_op<AsyncRandomAccessReadDevice, Allocator,
|
|
CompletionCondition, ReadHandler>* this_handler)
|
|
{
|
|
#if defined(ASIO_NO_DEPRECATED)
|
|
asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
|
|
return asio_handler_allocate_is_no_longer_used();
|
|
#else // defined(ASIO_NO_DEPRECATED)
|
|
return asio_handler_alloc_helpers::allocate(
|
|
size, this_handler->handler_);
|
|
#endif // defined(ASIO_NO_DEPRECATED)
|
|
}
|
|
|
|
template <typename AsyncRandomAccessReadDevice, typename Allocator,
|
|
typename CompletionCondition, typename ReadHandler>
|
|
inline asio_handler_deallocate_is_deprecated
|
|
asio_handler_deallocate(void* pointer, std::size_t size,
|
|
read_at_streambuf_op<AsyncRandomAccessReadDevice, Allocator,
|
|
CompletionCondition, ReadHandler>* this_handler)
|
|
{
|
|
asio_handler_alloc_helpers::deallocate(
|
|
pointer, size, this_handler->handler_);
|
|
#if defined(ASIO_NO_DEPRECATED)
|
|
return asio_handler_deallocate_is_no_longer_used();
|
|
#endif // defined(ASIO_NO_DEPRECATED)
|
|
}
|
|
|
|
template <typename AsyncRandomAccessReadDevice, typename Allocator,
|
|
typename CompletionCondition, typename ReadHandler>
|
|
inline bool asio_handler_is_continuation(
|
|
read_at_streambuf_op<AsyncRandomAccessReadDevice, Allocator,
|
|
CompletionCondition, ReadHandler>* this_handler)
|
|
{
|
|
return this_handler->start_ == 0 ? true
|
|
: asio_handler_cont_helpers::is_continuation(
|
|
this_handler->handler_);
|
|
}
|
|
|
|
template <typename Function, typename AsyncRandomAccessReadDevice,
|
|
typename Allocator, typename CompletionCondition, typename ReadHandler>
|
|
inline asio_handler_invoke_is_deprecated
|
|
asio_handler_invoke(Function& function,
|
|
read_at_streambuf_op<AsyncRandomAccessReadDevice, Allocator,
|
|
CompletionCondition, ReadHandler>* this_handler)
|
|
{
|
|
asio_handler_invoke_helpers::invoke(
|
|
function, this_handler->handler_);
|
|
#if defined(ASIO_NO_DEPRECATED)
|
|
return asio_handler_invoke_is_no_longer_used();
|
|
#endif // defined(ASIO_NO_DEPRECATED)
|
|
}
|
|
|
|
template <typename Function, typename AsyncRandomAccessReadDevice,
|
|
typename Allocator, typename CompletionCondition, typename ReadHandler>
|
|
inline asio_handler_invoke_is_deprecated
|
|
asio_handler_invoke(const Function& function,
|
|
read_at_streambuf_op<AsyncRandomAccessReadDevice, Allocator,
|
|
CompletionCondition, ReadHandler>* this_handler)
|
|
{
|
|
asio_handler_invoke_helpers::invoke(
|
|
function, this_handler->handler_);
|
|
#if defined(ASIO_NO_DEPRECATED)
|
|
return asio_handler_invoke_is_no_longer_used();
|
|
#endif // defined(ASIO_NO_DEPRECATED)
|
|
}
|
|
|
|
template <typename AsyncRandomAccessReadDevice>
|
|
class initiate_async_read_at_streambuf
|
|
{
|
|
public:
|
|
typedef typename AsyncRandomAccessReadDevice::executor_type executor_type;
|
|
|
|
explicit initiate_async_read_at_streambuf(
|
|
AsyncRandomAccessReadDevice& device)
|
|
: device_(device)
|
|
{
|
|
}
|
|
|
|
executor_type get_executor() const ASIO_NOEXCEPT
|
|
{
|
|
return device_.get_executor();
|
|
}
|
|
|
|
template <typename ReadHandler,
|
|
typename Allocator, typename CompletionCondition>
|
|
void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
|
|
uint64_t offset, basic_streambuf<Allocator>* b,
|
|
ASIO_MOVE_ARG(CompletionCondition) completion_cond) const
|
|
{
|
|
// If you get an error on the following line it means that your handler
|
|
// does not meet the documented type requirements for a ReadHandler.
|
|
ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
|
|
|
|
non_const_lvalue<ReadHandler> handler2(handler);
|
|
non_const_lvalue<CompletionCondition> completion_cond2(completion_cond);
|
|
read_at_streambuf_op<AsyncRandomAccessReadDevice, Allocator,
|
|
CompletionCondition, typename decay<ReadHandler>::type>(
|
|
device_, offset, *b, completion_cond2.value, handler2.value)(
|
|
asio::error_code(), 0, 1);
|
|
}
|
|
|
|
private:
|
|
AsyncRandomAccessReadDevice& device_;
|
|
};
|
|
} // namespace detail
|
|
|
|
#if !defined(GENERATING_DOCUMENTATION)
|
|
|
|
template <template <typename, typename> class Associator,
|
|
typename AsyncRandomAccessReadDevice, typename Executor,
|
|
typename CompletionCondition, typename ReadHandler,
|
|
typename DefaultCandidate>
|
|
struct associator<Associator,
|
|
detail::read_at_streambuf_op<AsyncRandomAccessReadDevice,
|
|
Executor, CompletionCondition, ReadHandler>,
|
|
DefaultCandidate>
|
|
: Associator<ReadHandler, DefaultCandidate>
|
|
{
|
|
static typename Associator<ReadHandler, DefaultCandidate>::type
|
|
get(const detail::read_at_streambuf_op<AsyncRandomAccessReadDevice,
|
|
Executor, CompletionCondition, ReadHandler>& h) ASIO_NOEXCEPT
|
|
{
|
|
return Associator<ReadHandler, DefaultCandidate>::get(h.handler_);
|
|
}
|
|
|
|
static ASIO_AUTO_RETURN_TYPE_PREFIX2(
|
|
typename Associator<ReadHandler, DefaultCandidate>::type)
|
|
get(const detail::read_at_streambuf_op<AsyncRandomAccessReadDevice,
|
|
Executor, CompletionCondition, ReadHandler>& h,
|
|
const DefaultCandidate& c) ASIO_NOEXCEPT
|
|
ASIO_AUTO_RETURN_TYPE_SUFFIX((
|
|
Associator<ReadHandler, DefaultCandidate>::get(h.handler_, c)))
|
|
{
|
|
return Associator<ReadHandler, DefaultCandidate>::get(h.handler_, c);
|
|
}
|
|
};
|
|
|
|
#endif // !defined(GENERATING_DOCUMENTATION)
|
|
|
|
template <typename AsyncRandomAccessReadDevice,
|
|
typename Allocator, typename CompletionCondition,
|
|
ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
|
|
std::size_t)) ReadToken>
|
|
inline ASIO_INITFN_AUTO_RESULT_TYPE_PREFIX(ReadToken,
|
|
void (asio::error_code, std::size_t))
|
|
async_read_at(AsyncRandomAccessReadDevice& d,
|
|
uint64_t offset, asio::basic_streambuf<Allocator>& b,
|
|
CompletionCondition completion_condition,
|
|
ASIO_MOVE_ARG(ReadToken) token)
|
|
ASIO_INITFN_AUTO_RESULT_TYPE_SUFFIX((
|
|
async_initiate<ReadToken,
|
|
void (asio::error_code, std::size_t)>(
|
|
declval<detail::initiate_async_read_at_streambuf<
|
|
AsyncRandomAccessReadDevice> >(),
|
|
token, offset, &b,
|
|
ASIO_MOVE_CAST(CompletionCondition)(completion_condition))))
|
|
{
|
|
return async_initiate<ReadToken,
|
|
void (asio::error_code, std::size_t)>(
|
|
detail::initiate_async_read_at_streambuf<AsyncRandomAccessReadDevice>(d),
|
|
token, offset, &b,
|
|
ASIO_MOVE_CAST(CompletionCondition)(completion_condition));
|
|
}
|
|
|
|
template <typename AsyncRandomAccessReadDevice, typename Allocator,
|
|
ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
|
|
std::size_t)) ReadToken>
|
|
inline ASIO_INITFN_AUTO_RESULT_TYPE_PREFIX(ReadToken,
|
|
void (asio::error_code, std::size_t))
|
|
async_read_at(AsyncRandomAccessReadDevice& d,
|
|
uint64_t offset, asio::basic_streambuf<Allocator>& b,
|
|
ASIO_MOVE_ARG(ReadToken) token)
|
|
ASIO_INITFN_AUTO_RESULT_TYPE_SUFFIX((
|
|
async_initiate<ReadToken,
|
|
void (asio::error_code, std::size_t)>(
|
|
declval<detail::initiate_async_read_at_streambuf<
|
|
AsyncRandomAccessReadDevice> >(),
|
|
token, offset, &b, transfer_all())))
|
|
{
|
|
return async_initiate<ReadToken,
|
|
void (asio::error_code, std::size_t)>(
|
|
detail::initiate_async_read_at_streambuf<AsyncRandomAccessReadDevice>(d),
|
|
token, offset, &b, transfer_all());
|
|
}
|
|
|
|
#endif // !defined(ASIO_NO_IOSTREAM)
|
|
#endif // !defined(ASIO_NO_EXTENSIONS)
|
|
|
|
} // namespace asio
|
|
|
|
#include "asio/detail/pop_options.hpp"
|
|
|
|
#endif // ASIO_IMPL_READ_AT_HPP
|