// // impl/read.hpp // ~~~~~~~~~~~~~ // // Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com) // // 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) // #ifndef BOOST_ASIO_IMPL_READ_HPP #define BOOST_ASIO_IMPL_READ_HPP #if defined(_MSC_VER) && (_MSC_VER >= 1200) # pragma once #endif // defined(_MSC_VER) && (_MSC_VER >= 1200) #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include namespace boost { namespace asio { namespace detail { template std::size_t read_buffer_sequence(SyncReadStream& s, const MutableBufferSequence& buffers, const MutableBufferIterator&, CompletionCondition completion_condition, boost::system::error_code& ec) { ec = boost::system::error_code(); boost::asio::detail::consuming_buffers tmp(buffers); while (!tmp.empty()) { if (std::size_t max_size = detail::adapt_completion_condition_result( completion_condition(ec, tmp.total_consumed()))) tmp.consume(s.read_some(tmp.prepare(max_size), ec)); else break; } return tmp.total_consumed(); } } // namespace detail template std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers, CompletionCondition completion_condition, boost::system::error_code& ec, typename constraint< is_mutable_buffer_sequence::value >::type) { return detail::read_buffer_sequence(s, buffers, boost::asio::buffer_sequence_begin(buffers), BOOST_ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec); } template inline std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers, typename constraint< is_mutable_buffer_sequence::value >::type) { boost::system::error_code ec; std::size_t bytes_transferred = read(s, buffers, transfer_all(), ec); boost::asio::detail::throw_error(ec, "read"); return bytes_transferred; } template inline std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers, boost::system::error_code& ec, typename constraint< is_mutable_buffer_sequence::value >::type) { return read(s, buffers, transfer_all(), ec); } template inline std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers, CompletionCondition completion_condition, typename constraint< is_mutable_buffer_sequence::value >::type) { boost::system::error_code ec; std::size_t bytes_transferred = read(s, buffers, BOOST_ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec); boost::asio::detail::throw_error(ec, "read"); return bytes_transferred; } #if !defined(BOOST_ASIO_NO_DYNAMIC_BUFFER_V1) template std::size_t read(SyncReadStream& s, BOOST_ASIO_MOVE_ARG(DynamicBuffer_v1) buffers, CompletionCondition completion_condition, boost::system::error_code& ec, typename constraint< is_dynamic_buffer_v1::type>::value >::type, typename constraint< !is_dynamic_buffer_v2::type>::value >::type) { typename decay::type b( BOOST_ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers)); ec = boost::system::error_code(); std::size_t total_transferred = 0; std::size_t max_size = detail::adapt_completion_condition_result( completion_condition(ec, total_transferred)); std::size_t bytes_available = std::min( std::max(512, b.capacity() - b.size()), std::min(max_size, b.max_size() - b.size())); while (bytes_available > 0) { std::size_t bytes_transferred = s.read_some(b.prepare(bytes_available), ec); b.commit(bytes_transferred); total_transferred += bytes_transferred; max_size = detail::adapt_completion_condition_result( completion_condition(ec, total_transferred)); bytes_available = std::min( std::max(512, b.capacity() - b.size()), std::min(max_size, b.max_size() - b.size())); } return total_transferred; } template inline std::size_t read(SyncReadStream& s, BOOST_ASIO_MOVE_ARG(DynamicBuffer_v1) buffers, typename constraint< is_dynamic_buffer_v1::type>::value >::type, typename constraint< !is_dynamic_buffer_v2::type>::value >::type) { boost::system::error_code ec; std::size_t bytes_transferred = read(s, BOOST_ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers), transfer_all(), ec); boost::asio::detail::throw_error(ec, "read"); return bytes_transferred; } template inline std::size_t read(SyncReadStream& s, BOOST_ASIO_MOVE_ARG(DynamicBuffer_v1) buffers, boost::system::error_code& ec, typename constraint< is_dynamic_buffer_v1::type>::value >::type, typename constraint< !is_dynamic_buffer_v2::type>::value >::type) { return read(s, BOOST_ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers), transfer_all(), ec); } template inline std::size_t read(SyncReadStream& s, BOOST_ASIO_MOVE_ARG(DynamicBuffer_v1) buffers, CompletionCondition completion_condition, typename constraint< is_dynamic_buffer_v1::type>::value >::type, typename constraint< !is_dynamic_buffer_v2::type>::value >::type) { boost::system::error_code ec; std::size_t bytes_transferred = read(s, BOOST_ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers), BOOST_ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec); boost::asio::detail::throw_error(ec, "read"); return bytes_transferred; } #if !defined(BOOST_ASIO_NO_EXTENSIONS) #if !defined(BOOST_ASIO_NO_IOSTREAM) template inline std::size_t read(SyncReadStream& s, boost::asio::basic_streambuf& b, CompletionCondition completion_condition, boost::system::error_code& ec) { return read(s, basic_streambuf_ref(b), BOOST_ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec); } template inline std::size_t read(SyncReadStream& s, boost::asio::basic_streambuf& b) { return read(s, basic_streambuf_ref(b)); } template inline std::size_t read(SyncReadStream& s, boost::asio::basic_streambuf& b, boost::system::error_code& ec) { return read(s, basic_streambuf_ref(b), ec); } template inline std::size_t read(SyncReadStream& s, boost::asio::basic_streambuf& b, CompletionCondition completion_condition) { return read(s, basic_streambuf_ref(b), BOOST_ASIO_MOVE_CAST(CompletionCondition)(completion_condition)); } #endif // !defined(BOOST_ASIO_NO_IOSTREAM) #endif // !defined(BOOST_ASIO_NO_EXTENSIONS) #endif // !defined(BOOST_ASIO_NO_DYNAMIC_BUFFER_V1) template std::size_t read(SyncReadStream& s, DynamicBuffer_v2 buffers, CompletionCondition completion_condition, boost::system::error_code& ec, typename constraint< is_dynamic_buffer_v2::value >::type) { DynamicBuffer_v2& b = buffers; ec = boost::system::error_code(); std::size_t total_transferred = 0; std::size_t max_size = detail::adapt_completion_condition_result( completion_condition(ec, total_transferred)); std::size_t bytes_available = std::min( std::max(512, b.capacity() - b.size()), std::min(max_size, b.max_size() - b.size())); while (bytes_available > 0) { std::size_t pos = b.size(); b.grow(bytes_available); std::size_t bytes_transferred = s.read_some( b.data(pos, bytes_available), ec); b.shrink(bytes_available - bytes_transferred); total_transferred += bytes_transferred; max_size = detail::adapt_completion_condition_result( completion_condition(ec, total_transferred)); bytes_available = std::min( std::max(512, b.capacity() - b.size()), std::min(max_size, b.max_size() - b.size())); } return total_transferred; } template inline std::size_t read(SyncReadStream& s, DynamicBuffer_v2 buffers, typename constraint< is_dynamic_buffer_v2::value >::type) { boost::system::error_code ec; std::size_t bytes_transferred = read(s, BOOST_ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers), transfer_all(), ec); boost::asio::detail::throw_error(ec, "read"); return bytes_transferred; } template inline std::size_t read(SyncReadStream& s, DynamicBuffer_v2 buffers, boost::system::error_code& ec, typename constraint< is_dynamic_buffer_v2::value >::type) { return read(s, BOOST_ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers), transfer_all(), ec); } template inline std::size_t read(SyncReadStream& s, DynamicBuffer_v2 buffers, CompletionCondition completion_condition, typename constraint< is_dynamic_buffer_v2::value >::type) { boost::system::error_code ec; std::size_t bytes_transferred = read(s, BOOST_ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers), BOOST_ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec); boost::asio::detail::throw_error(ec, "read"); return bytes_transferred; } namespace detail { template class read_op : public base_from_cancellation_state, base_from_completion_cond { public: read_op(AsyncReadStream& stream, const MutableBufferSequence& buffers, CompletionCondition& completion_condition, ReadHandler& handler) : base_from_cancellation_state( handler, enable_partial_cancellation()), base_from_completion_cond(completion_condition), stream_(stream), buffers_(buffers), start_(0), handler_(BOOST_ASIO_MOVE_CAST(ReadHandler)(handler)) { } #if defined(BOOST_ASIO_HAS_MOVE) read_op(const read_op& other) : base_from_cancellation_state(other), base_from_completion_cond(other), stream_(other.stream_), buffers_(other.buffers_), start_(other.start_), handler_(other.handler_) { } read_op(read_op&& other) : base_from_cancellation_state( BOOST_ASIO_MOVE_CAST(base_from_cancellation_state< ReadHandler>)(other)), base_from_completion_cond( BOOST_ASIO_MOVE_CAST(base_from_completion_cond< CompletionCondition>)(other)), stream_(other.stream_), buffers_(BOOST_ASIO_MOVE_CAST(buffers_type)(other.buffers_)), start_(other.start_), handler_(BOOST_ASIO_MOVE_CAST(ReadHandler)(other.handler_)) { } #endif // defined(BOOST_ASIO_HAS_MOVE) void operator()(boost::system::error_code ec, std::size_t bytes_transferred, int start = 0) { std::size_t max_size; switch (start_ = start) { case 1: max_size = this->check_for_completion(ec, buffers_.total_consumed()); for (;;) { { BOOST_ASIO_HANDLER_LOCATION((__FILE__, __LINE__, "async_read")); stream_.async_read_some(buffers_.prepare(max_size), BOOST_ASIO_MOVE_CAST(read_op)(*this)); } return; default: buffers_.consume(bytes_transferred); if ((!ec && bytes_transferred == 0) || buffers_.empty()) break; max_size = this->check_for_completion(ec, buffers_.total_consumed()); if (max_size == 0) break; if (this->cancelled() != cancellation_type::none) { ec = error::operation_aborted; break; } } BOOST_ASIO_MOVE_OR_LVALUE(ReadHandler)(handler_)( static_cast(ec), static_cast(buffers_.total_consumed())); } } //private: typedef boost::asio::detail::consuming_buffers buffers_type; AsyncReadStream& stream_; buffers_type buffers_; int start_; ReadHandler handler_; }; template inline asio_handler_allocate_is_deprecated asio_handler_allocate(std::size_t size, read_op* this_handler) { #if defined(BOOST_ASIO_NO_DEPRECATED) boost_asio_handler_alloc_helpers::allocate(size, this_handler->handler_); return asio_handler_allocate_is_no_longer_used(); #else // defined(BOOST_ASIO_NO_DEPRECATED) return boost_asio_handler_alloc_helpers::allocate( size, this_handler->handler_); #endif // defined(BOOST_ASIO_NO_DEPRECATED) } template inline asio_handler_deallocate_is_deprecated asio_handler_deallocate(void* pointer, std::size_t size, read_op* this_handler) { boost_asio_handler_alloc_helpers::deallocate( pointer, size, this_handler->handler_); #if defined(BOOST_ASIO_NO_DEPRECATED) return asio_handler_deallocate_is_no_longer_used(); #endif // defined(BOOST_ASIO_NO_DEPRECATED) } template inline bool asio_handler_is_continuation( read_op* this_handler) { return this_handler->start_ == 0 ? true : boost_asio_handler_cont_helpers::is_continuation( this_handler->handler_); } template inline asio_handler_invoke_is_deprecated asio_handler_invoke(Function& function, read_op* this_handler) { boost_asio_handler_invoke_helpers::invoke( function, this_handler->handler_); #if defined(BOOST_ASIO_NO_DEPRECATED) return asio_handler_invoke_is_no_longer_used(); #endif // defined(BOOST_ASIO_NO_DEPRECATED) } template inline asio_handler_invoke_is_deprecated asio_handler_invoke(const Function& function, read_op* this_handler) { boost_asio_handler_invoke_helpers::invoke( function, this_handler->handler_); #if defined(BOOST_ASIO_NO_DEPRECATED) return asio_handler_invoke_is_no_longer_used(); #endif // defined(BOOST_ASIO_NO_DEPRECATED) } template inline void start_read_buffer_sequence_op(AsyncReadStream& stream, const MutableBufferSequence& buffers, const MutableBufferIterator&, CompletionCondition& completion_condition, ReadHandler& handler) { detail::read_op( stream, buffers, completion_condition, handler)( boost::system::error_code(), 0, 1); } template class initiate_async_read_buffer_sequence { public: typedef typename AsyncReadStream::executor_type executor_type; explicit initiate_async_read_buffer_sequence(AsyncReadStream& stream) : stream_(stream) { } executor_type get_executor() const BOOST_ASIO_NOEXCEPT { return stream_.get_executor(); } template void operator()(BOOST_ASIO_MOVE_ARG(ReadHandler) handler, const MutableBufferSequence& buffers, BOOST_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. BOOST_ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check; non_const_lvalue handler2(handler); non_const_lvalue completion_cond2(completion_cond); start_read_buffer_sequence_op(stream_, buffers, boost::asio::buffer_sequence_begin(buffers), completion_cond2.value, handler2.value); } private: AsyncReadStream& stream_; }; } // namespace detail #if !defined(GENERATING_DOCUMENTATION) template