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+//
+// detail/win_iocp_socket_service_base.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2018 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 ASIO_DETAIL_WIN_IOCP_SOCKET_SERVICE_BASE_HPP
+#define ASIO_DETAIL_WIN_IOCP_SOCKET_SERVICE_BASE_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include "asio/detail/config.hpp"
+
+#if defined(ASIO_HAS_IOCP)
+
+#include "asio/error.hpp"
+#include "asio/io_context.hpp"
+#include "asio/socket_base.hpp"
+#include "asio/detail/bind_handler.hpp"
+#include "asio/detail/buffer_sequence_adapter.hpp"
+#include "asio/detail/fenced_block.hpp"
+#include "asio/detail/handler_alloc_helpers.hpp"
+#include "asio/detail/handler_invoke_helpers.hpp"
+#include "asio/detail/memory.hpp"
+#include "asio/detail/mutex.hpp"
+#include "asio/detail/operation.hpp"
+#include "asio/detail/reactor_op.hpp"
+#include "asio/detail/select_reactor.hpp"
+#include "asio/detail/socket_holder.hpp"
+#include "asio/detail/socket_ops.hpp"
+#include "asio/detail/socket_types.hpp"
+#include "asio/detail/win_iocp_io_context.hpp"
+#include "asio/detail/win_iocp_null_buffers_op.hpp"
+#include "asio/detail/win_iocp_socket_connect_op.hpp"
+#include "asio/detail/win_iocp_socket_send_op.hpp"
+#include "asio/detail/win_iocp_socket_recv_op.hpp"
+#include "asio/detail/win_iocp_socket_recvmsg_op.hpp"
+#include "asio/detail/win_iocp_wait_op.hpp"
+
+#include "asio/detail/push_options.hpp"
+
+namespace asio {
+namespace detail {
+
+class win_iocp_socket_service_base
+{
+public:
+ // The implementation type of the socket.
+ struct base_implementation_type
+ {
+ // The native socket representation.
+ socket_type socket_;
+
+ // The current state of the socket.
+ socket_ops::state_type state_;
+
+ // We use a shared pointer as a cancellation token here to work around the
+ // broken Windows support for cancellation. MSDN says that when you call
+ // closesocket any outstanding WSARecv or WSASend operations will complete
+ // with the error ERROR_OPERATION_ABORTED. In practice they complete with
+ // ERROR_NETNAME_DELETED, which means you can't tell the difference between
+ // a local cancellation and the socket being hard-closed by the peer.
+ socket_ops::shared_cancel_token_type cancel_token_;
+
+ // Per-descriptor data used by the reactor.
+ select_reactor::per_descriptor_data reactor_data_;
+
+#if defined(ASIO_ENABLE_CANCELIO)
+ // The ID of the thread from which it is safe to cancel asynchronous
+ // operations. 0 means no asynchronous operations have been started yet.
+ // ~0 means asynchronous operations have been started from more than one
+ // thread, and cancellation is not supported for the socket.
+ DWORD safe_cancellation_thread_id_;
+#endif // defined(ASIO_ENABLE_CANCELIO)
+
+ // Pointers to adjacent socket implementations in linked list.
+ base_implementation_type* next_;
+ base_implementation_type* prev_;
+ };
+
+ // Constructor.
+ ASIO_DECL win_iocp_socket_service_base(
+ asio::io_context& io_context);
+
+ // Destroy all user-defined handler objects owned by the service.
+ ASIO_DECL void base_shutdown();
+
+ // Construct a new socket implementation.
+ ASIO_DECL void construct(base_implementation_type& impl);
+
+ // Move-construct a new socket implementation.
+ ASIO_DECL void base_move_construct(base_implementation_type& impl,
+ base_implementation_type& other_impl);
+
+ // Move-assign from another socket implementation.
+ ASIO_DECL void base_move_assign(base_implementation_type& impl,
+ win_iocp_socket_service_base& other_service,
+ base_implementation_type& other_impl);
+
+ // Destroy a socket implementation.
+ ASIO_DECL void destroy(base_implementation_type& impl);
+
+ // Determine whether the socket is open.
+ bool is_open(const base_implementation_type& impl) const
+ {
+ return impl.socket_ != invalid_socket;
+ }
+
+ // Destroy a socket implementation.
+ ASIO_DECL asio::error_code close(
+ base_implementation_type& impl, asio::error_code& ec);
+
+ // Release ownership of the socket.
+ ASIO_DECL socket_type release(
+ base_implementation_type& impl, asio::error_code& ec);
+
+ // Cancel all operations associated with the socket.
+ ASIO_DECL asio::error_code cancel(
+ base_implementation_type& impl, asio::error_code& ec);
+
+ // Determine whether the socket is at the out-of-band data mark.
+ bool at_mark(const base_implementation_type& impl,
+ asio::error_code& ec) const
+ {
+ return socket_ops::sockatmark(impl.socket_, ec);
+ }
+
+ // Determine the number of bytes available for reading.
+ std::size_t available(const base_implementation_type& impl,
+ asio::error_code& ec) const
+ {
+ return socket_ops::available(impl.socket_, ec);
+ }
+
+ // Place the socket into the state where it will listen for new connections.
+ asio::error_code listen(base_implementation_type& impl,
+ int backlog, asio::error_code& ec)
+ {
+ socket_ops::listen(impl.socket_, backlog, ec);
+ return ec;
+ }
+
+ // Perform an IO control command on the socket.
+ template <typename IO_Control_Command>
+ asio::error_code io_control(base_implementation_type& impl,
+ IO_Control_Command& command, asio::error_code& ec)
+ {
+ socket_ops::ioctl(impl.socket_, impl.state_, command.name(),
+ static_cast<ioctl_arg_type*>(command.data()), ec);
+ return ec;
+ }
+
+ // Gets the non-blocking mode of the socket.
+ bool non_blocking(const base_implementation_type& impl) const
+ {
+ return (impl.state_ & socket_ops::user_set_non_blocking) != 0;
+ }
+
+ // Sets the non-blocking mode of the socket.
+ asio::error_code non_blocking(base_implementation_type& impl,
+ bool mode, asio::error_code& ec)
+ {
+ socket_ops::set_user_non_blocking(impl.socket_, impl.state_, mode, ec);
+ return ec;
+ }
+
+ // Gets the non-blocking mode of the native socket implementation.
+ bool native_non_blocking(const base_implementation_type& impl) const
+ {
+ return (impl.state_ & socket_ops::internal_non_blocking) != 0;
+ }
+
+ // Sets the non-blocking mode of the native socket implementation.
+ asio::error_code native_non_blocking(base_implementation_type& impl,
+ bool mode, asio::error_code& ec)
+ {
+ socket_ops::set_internal_non_blocking(impl.socket_, impl.state_, mode, ec);
+ return ec;
+ }
+
+ // Wait for the socket to become ready to read, ready to write, or to have
+ // pending error conditions.
+ asio::error_code wait(base_implementation_type& impl,
+ socket_base::wait_type w, asio::error_code& ec)
+ {
+ switch (w)
+ {
+ case socket_base::wait_read:
+ socket_ops::poll_read(impl.socket_, impl.state_, -1, ec);
+ break;
+ case socket_base::wait_write:
+ socket_ops::poll_write(impl.socket_, impl.state_, -1, ec);
+ break;
+ case socket_base::wait_error:
+ socket_ops::poll_error(impl.socket_, impl.state_, -1, ec);
+ break;
+ default:
+ ec = asio::error::invalid_argument;
+ break;
+ }
+
+ return ec;
+ }
+
+ // Asynchronously wait for the socket to become ready to read, ready to
+ // write, or to have pending error conditions.
+ template <typename Handler>
+ void async_wait(base_implementation_type& impl,
+ socket_base::wait_type w, Handler& handler)
+ {
+ bool is_continuation =
+ asio_handler_cont_helpers::is_continuation(handler);
+
+ // Allocate and construct an operation to wrap the handler.
+ typedef win_iocp_wait_op<Handler> op;
+ typename op::ptr p = { asio::detail::addressof(handler),
+ op::ptr::allocate(handler), 0 };
+ p.p = new (p.v) op(impl.cancel_token_, handler);
+
+ ASIO_HANDLER_CREATION((io_context_, *p.p, "socket",
+ &impl, impl.socket_, "async_wait"));
+
+ switch (w)
+ {
+ case socket_base::wait_read:
+ start_null_buffers_receive_op(impl, 0, p.p);
+ break;
+ case socket_base::wait_write:
+ start_reactor_op(impl, select_reactor::write_op, p.p);
+ break;
+ case socket_base::wait_error:
+ start_reactor_op(impl, select_reactor::except_op, p.p);
+ break;
+ default:
+ p.p->ec_ = asio::error::invalid_argument;
+ iocp_service_.post_immediate_completion(p.p, is_continuation);
+ break;
+ }
+
+ p.v = p.p = 0;
+ }
+
+ // Send the given data to the peer. Returns the number of bytes sent.
+ template <typename ConstBufferSequence>
+ size_t send(base_implementation_type& impl,
+ const ConstBufferSequence& buffers,
+ socket_base::message_flags flags, asio::error_code& ec)
+ {
+ buffer_sequence_adapter<asio::const_buffer,
+ ConstBufferSequence> bufs(buffers);
+
+ return socket_ops::sync_send(impl.socket_, impl.state_,
+ bufs.buffers(), bufs.count(), flags, bufs.all_empty(), ec);
+ }
+
+ // Wait until data can be sent without blocking.
+ size_t send(base_implementation_type& impl, const null_buffers&,
+ socket_base::message_flags, asio::error_code& ec)
+ {
+ // Wait for socket to become ready.
+ socket_ops::poll_write(impl.socket_, impl.state_, -1, ec);
+
+ return 0;
+ }
+
+ // Start an asynchronous send. The data being sent must be valid for the
+ // lifetime of the asynchronous operation.
+ template <typename ConstBufferSequence, typename Handler>
+ void async_send(base_implementation_type& impl,
+ const ConstBufferSequence& buffers,
+ socket_base::message_flags flags, Handler& handler)
+ {
+ // Allocate and construct an operation to wrap the handler.
+ typedef win_iocp_socket_send_op<ConstBufferSequence, Handler> op;
+ typename op::ptr p = { asio::detail::addressof(handler),
+ op::ptr::allocate(handler), 0 };
+ p.p = new (p.v) op(impl.cancel_token_, buffers, handler);
+
+ ASIO_HANDLER_CREATION((io_context_, *p.p, "socket",
+ &impl, impl.socket_, "async_send"));
+
+ buffer_sequence_adapter<asio::const_buffer,
+ ConstBufferSequence> bufs(buffers);
+
+ start_send_op(impl, bufs.buffers(), bufs.count(), flags,
+ (impl.state_ & socket_ops::stream_oriented) != 0 && bufs.all_empty(),
+ p.p);
+ p.v = p.p = 0;
+ }
+
+ // Start an asynchronous wait until data can be sent without blocking.
+ template <typename Handler>
+ void async_send(base_implementation_type& impl, const null_buffers&,
+ socket_base::message_flags, Handler& handler)
+ {
+ // Allocate and construct an operation to wrap the handler.
+ typedef win_iocp_null_buffers_op<Handler> op;
+ typename op::ptr p = { asio::detail::addressof(handler),
+ op::ptr::allocate(handler), 0 };
+ p.p = new (p.v) op(impl.cancel_token_, handler);
+
+ ASIO_HANDLER_CREATION((io_context_, *p.p, "socket",
+ &impl, impl.socket_, "async_send(null_buffers)"));
+
+ start_reactor_op(impl, select_reactor::write_op, p.p);
+ p.v = p.p = 0;
+ }
+
+ // Receive some data from the peer. Returns the number of bytes received.
+ template <typename MutableBufferSequence>
+ size_t receive(base_implementation_type& impl,
+ const MutableBufferSequence& buffers,
+ socket_base::message_flags flags, asio::error_code& ec)
+ {
+ buffer_sequence_adapter<asio::mutable_buffer,
+ MutableBufferSequence> bufs(buffers);
+
+ return socket_ops::sync_recv(impl.socket_, impl.state_,
+ bufs.buffers(), bufs.count(), flags, bufs.all_empty(), ec);
+ }
+
+ // Wait until data can be received without blocking.
+ size_t receive(base_implementation_type& impl, const null_buffers&,
+ socket_base::message_flags, asio::error_code& ec)
+ {
+ // Wait for socket to become ready.
+ socket_ops::poll_read(impl.socket_, impl.state_, -1, ec);
+
+ return 0;
+ }
+
+ // Start an asynchronous receive. The buffer for the data being received
+ // must be valid for the lifetime of the asynchronous operation.
+ template <typename MutableBufferSequence, typename Handler>
+ void async_receive(base_implementation_type& impl,
+ const MutableBufferSequence& buffers,
+ socket_base::message_flags flags, Handler& handler)
+ {
+ // Allocate and construct an operation to wrap the handler.
+ typedef win_iocp_socket_recv_op<MutableBufferSequence, Handler> op;
+ typename op::ptr p = { asio::detail::addressof(handler),
+ op::ptr::allocate(handler), 0 };
+ p.p = new (p.v) op(impl.state_, impl.cancel_token_, buffers, handler);
+
+ ASIO_HANDLER_CREATION((io_context_, *p.p, "socket",
+ &impl, impl.socket_, "async_receive"));
+
+ buffer_sequence_adapter<asio::mutable_buffer,
+ MutableBufferSequence> bufs(buffers);
+
+ start_receive_op(impl, bufs.buffers(), bufs.count(), flags,
+ (impl.state_ & socket_ops::stream_oriented) != 0 && bufs.all_empty(),
+ p.p);
+ p.v = p.p = 0;
+ }
+
+ // Wait until data can be received without blocking.
+ template <typename Handler>
+ void async_receive(base_implementation_type& impl, const null_buffers&,
+ socket_base::message_flags flags, Handler& handler)
+ {
+ // Allocate and construct an operation to wrap the handler.
+ typedef win_iocp_null_buffers_op<Handler> op;
+ typename op::ptr p = { asio::detail::addressof(handler),
+ op::ptr::allocate(handler), 0 };
+ p.p = new (p.v) op(impl.cancel_token_, handler);
+
+ ASIO_HANDLER_CREATION((io_context_, *p.p, "socket",
+ &impl, impl.socket_, "async_receive(null_buffers)"));
+
+ start_null_buffers_receive_op(impl, flags, p.p);
+ p.v = p.p = 0;
+ }
+
+ // Receive some data with associated flags. Returns the number of bytes
+ // received.
+ template <typename MutableBufferSequence>
+ size_t receive_with_flags(base_implementation_type& impl,
+ const MutableBufferSequence& buffers,
+ socket_base::message_flags in_flags,
+ socket_base::message_flags& out_flags, asio::error_code& ec)
+ {
+ buffer_sequence_adapter<asio::mutable_buffer,
+ MutableBufferSequence> bufs(buffers);
+
+ return socket_ops::sync_recvmsg(impl.socket_, impl.state_,
+ bufs.buffers(), bufs.count(), in_flags, out_flags, ec);
+ }
+
+ // Wait until data can be received without blocking.
+ size_t receive_with_flags(base_implementation_type& impl,
+ const null_buffers&, socket_base::message_flags,
+ socket_base::message_flags& out_flags, asio::error_code& ec)
+ {
+ // Wait for socket to become ready.
+ socket_ops::poll_read(impl.socket_, impl.state_, -1, ec);
+
+ // Clear out_flags, since we cannot give it any other sensible value when
+ // performing a null_buffers operation.
+ out_flags = 0;
+
+ return 0;
+ }
+
+ // Start an asynchronous receive. The buffer for the data being received
+ // must be valid for the lifetime of the asynchronous operation.
+ template <typename MutableBufferSequence, typename Handler>
+ void async_receive_with_flags(base_implementation_type& impl,
+ const MutableBufferSequence& buffers, socket_base::message_flags in_flags,
+ socket_base::message_flags& out_flags, Handler& handler)
+ {
+ // Allocate and construct an operation to wrap the handler.
+ typedef win_iocp_socket_recvmsg_op<MutableBufferSequence, Handler> op;
+ typename op::ptr p = { asio::detail::addressof(handler),
+ op::ptr::allocate(handler), 0 };
+ p.p = new (p.v) op(impl.cancel_token_, buffers, out_flags, handler);
+
+ ASIO_HANDLER_CREATION((io_context_, *p.p, "socket",
+ &impl, impl.socket_, "async_receive_with_flags"));
+
+ buffer_sequence_adapter<asio::mutable_buffer,
+ MutableBufferSequence> bufs(buffers);
+
+ start_receive_op(impl, bufs.buffers(), bufs.count(), in_flags, false, p.p);
+ p.v = p.p = 0;
+ }
+
+ // Wait until data can be received without blocking.
+ template <typename Handler>
+ void async_receive_with_flags(base_implementation_type& impl,
+ const null_buffers&, socket_base::message_flags in_flags,
+ socket_base::message_flags& out_flags, Handler& handler)
+ {
+ // Allocate and construct an operation to wrap the handler.
+ typedef win_iocp_null_buffers_op<Handler> op;
+ typename op::ptr p = { asio::detail::addressof(handler),
+ op::ptr::allocate(handler), 0 };
+ p.p = new (p.v) op(impl.cancel_token_, handler);
+
+ ASIO_HANDLER_CREATION((io_context_, *p.p, "socket",
+ &impl, impl.socket_, "async_receive_with_flags(null_buffers)"));
+
+ // Reset out_flags since it can be given no sensible value at this time.
+ out_flags = 0;
+
+ start_null_buffers_receive_op(impl, in_flags, p.p);
+ p.v = p.p = 0;
+ }
+
+ // Helper function to restart an asynchronous accept operation.
+ ASIO_DECL void restart_accept_op(socket_type s,
+ socket_holder& new_socket, int family, int type, int protocol,
+ void* output_buffer, DWORD address_length, operation* op);
+
+protected:
+ // Open a new socket implementation.
+ ASIO_DECL asio::error_code do_open(
+ base_implementation_type& impl, int family, int type,
+ int protocol, asio::error_code& ec);
+
+ // Assign a native socket to a socket implementation.
+ ASIO_DECL asio::error_code do_assign(
+ base_implementation_type& impl, int type,
+ socket_type native_socket, asio::error_code& ec);
+
+ // Helper function to start an asynchronous send operation.
+ ASIO_DECL void start_send_op(base_implementation_type& impl,
+ WSABUF* buffers, std::size_t buffer_count,
+ socket_base::message_flags flags, bool noop, operation* op);
+
+ // Helper function to start an asynchronous send_to operation.
+ ASIO_DECL void start_send_to_op(base_implementation_type& impl,
+ WSABUF* buffers, std::size_t buffer_count,
+ const socket_addr_type* addr, int addrlen,
+ socket_base::message_flags flags, operation* op);
+
+ // Helper function to start an asynchronous receive operation.
+ ASIO_DECL void start_receive_op(base_implementation_type& impl,
+ WSABUF* buffers, std::size_t buffer_count,
+ socket_base::message_flags flags, bool noop, operation* op);
+
+ // Helper function to start an asynchronous null_buffers receive operation.
+ ASIO_DECL void start_null_buffers_receive_op(
+ base_implementation_type& impl,
+ socket_base::message_flags flags, reactor_op* op);
+
+ // Helper function to start an asynchronous receive_from operation.
+ ASIO_DECL void start_receive_from_op(base_implementation_type& impl,
+ WSABUF* buffers, std::size_t buffer_count, socket_addr_type* addr,
+ socket_base::message_flags flags, int* addrlen, operation* op);
+
+ // Helper function to start an asynchronous accept operation.
+ ASIO_DECL void start_accept_op(base_implementation_type& impl,
+ bool peer_is_open, socket_holder& new_socket, int family, int type,
+ int protocol, void* output_buffer, DWORD address_length, operation* op);
+
+ // Start an asynchronous read or write operation using the reactor.
+ ASIO_DECL void start_reactor_op(base_implementation_type& impl,
+ int op_type, reactor_op* op);
+
+ // Start the asynchronous connect operation using the reactor.
+ ASIO_DECL void start_connect_op(base_implementation_type& impl,
+ int family, int type, const socket_addr_type* remote_addr,
+ std::size_t remote_addrlen, win_iocp_socket_connect_op_base* op);
+
+ // Helper function to close a socket when the associated object is being
+ // destroyed.
+ ASIO_DECL void close_for_destruction(base_implementation_type& impl);
+
+ // Update the ID of the thread from which cancellation is safe.
+ ASIO_DECL void update_cancellation_thread_id(
+ base_implementation_type& impl);
+
+ // Helper function to get the reactor. If no reactor has been created yet, a
+ // new one is obtained from the io_context and a pointer to it is cached in
+ // this service.
+ ASIO_DECL select_reactor& get_reactor();
+
+ // The type of a ConnectEx function pointer, as old SDKs may not provide it.
+ typedef BOOL (PASCAL *connect_ex_fn)(SOCKET,
+ const socket_addr_type*, int, void*, DWORD, DWORD*, OVERLAPPED*);
+
+ // Helper function to get the ConnectEx pointer. If no ConnectEx pointer has
+ // been obtained yet, one is obtained using WSAIoctl and the pointer is
+ // cached. Returns a null pointer if ConnectEx is not available.
+ ASIO_DECL connect_ex_fn get_connect_ex(
+ base_implementation_type& impl, int type);
+
+ // The type of a NtSetInformationFile function pointer.
+ typedef LONG (NTAPI *nt_set_info_fn)(HANDLE, ULONG_PTR*, void*, ULONG, ULONG);
+
+ // Helper function to get the NtSetInformationFile function pointer. If no
+ // NtSetInformationFile pointer has been obtained yet, one is obtained using
+ // GetProcAddress and the pointer is cached. Returns a null pointer if
+ // NtSetInformationFile is not available.
+ ASIO_DECL nt_set_info_fn get_nt_set_info();
+
+ // Helper function to emulate InterlockedCompareExchangePointer functionality
+ // for:
+ // - very old Platform SDKs; and
+ // - platform SDKs where MSVC's /Wp64 option causes spurious warnings.
+ ASIO_DECL void* interlocked_compare_exchange_pointer(
+ void** dest, void* exch, void* cmp);
+
+ // Helper function to emulate InterlockedExchangePointer functionality for:
+ // - very old Platform SDKs; and
+ // - platform SDKs where MSVC's /Wp64 option causes spurious warnings.
+ ASIO_DECL void* interlocked_exchange_pointer(void** dest, void* val);
+
+ // The io_context used to obtain the reactor, if required.
+ asio::io_context& io_context_;
+
+ // The IOCP service used for running asynchronous operations and dispatching
+ // handlers.
+ win_iocp_io_context& iocp_service_;
+
+ // The reactor used for performing connect operations. This object is created
+ // only if needed.
+ select_reactor* reactor_;
+
+ // Pointer to ConnectEx implementation.
+ void* connect_ex_;
+
+ // Pointer to NtSetInformationFile implementation.
+ void* nt_set_info_;
+
+ // Mutex to protect access to the linked list of implementations.
+ asio::detail::mutex mutex_;
+
+ // The head of a linked list of all implementations.
+ base_implementation_type* impl_list_;
+};
+
+} // namespace detail
+} // namespace asio
+
+#include "asio/detail/pop_options.hpp"
+
+#if defined(ASIO_HEADER_ONLY)
+# include "asio/detail/impl/win_iocp_socket_service_base.ipp"
+#endif // defined(ASIO_HEADER_ONLY)
+
+#endif // defined(ASIO_HAS_IOCP)
+
+#endif // ASIO_DETAIL_WIN_IOCP_SOCKET_SERVICE_BASE_HPP