1 //
2 // detail/win_iocp_handle_service.hpp
3 // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4 //
5 // Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
6 // Copyright (c) 2008 Rep Invariant Systems, Inc. ([email protected])
7 //
8 // Distributed under the Boost Software License, Version 1.0. (See accompanying
9 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
10 //
11 
12 #ifndef BOOST_ASIO_DETAIL_WIN_IOCP_HANDLE_SERVICE_HPP
13 #define BOOST_ASIO_DETAIL_WIN_IOCP_HANDLE_SERVICE_HPP
14 
15 #if defined(_MSC_VER) && (_MSC_VER >= 1200)
16 # pragma once
17 #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
18 
19 #include <boost/asio/detail/config.hpp>
20 
21 #if defined(BOOST_ASIO_HAS_IOCP)
22 
23 #include <boost/asio/error.hpp>
24 #include <boost/asio/execution_context.hpp>
25 #include <boost/asio/detail/buffer_sequence_adapter.hpp>
26 #include <boost/asio/detail/cstdint.hpp>
27 #include <boost/asio/detail/handler_alloc_helpers.hpp>
28 #include <boost/asio/detail/memory.hpp>
29 #include <boost/asio/detail/mutex.hpp>
30 #include <boost/asio/detail/operation.hpp>
31 #include <boost/asio/detail/win_iocp_handle_read_op.hpp>
32 #include <boost/asio/detail/win_iocp_handle_write_op.hpp>
33 #include <boost/asio/detail/win_iocp_io_context.hpp>
34 
35 #include <boost/asio/detail/push_options.hpp>
36 
37 namespace boost {
38 namespace asio {
39 namespace detail {
40 
41 class win_iocp_handle_service :
42   public execution_context_service_base<win_iocp_handle_service>
43 {
44 public:
45   // The native type of a stream handle.
46   typedef HANDLE native_handle_type;
47 
48   // The implementation type of the stream handle.
49   class implementation_type
50   {
51   public:
52     // Default constructor.
implementation_type()53     implementation_type()
54       : handle_(INVALID_HANDLE_VALUE),
55         safe_cancellation_thread_id_(0),
56         next_(0),
57         prev_(0)
58     {
59     }
60 
61   private:
62     // Only this service will have access to the internal values.
63     friend class win_iocp_handle_service;
64 
65     // The native stream handle representation.
66     native_handle_type handle_;
67 
68     // The ID of the thread from which it is safe to cancel asynchronous
69     // operations. 0 means no asynchronous operations have been started yet.
70     // ~0 means asynchronous operations have been started from more than one
71     // thread, and cancellation is not supported for the handle.
72     DWORD safe_cancellation_thread_id_;
73 
74     // Pointers to adjacent handle implementations in linked list.
75     implementation_type* next_;
76     implementation_type* prev_;
77   };
78 
79   BOOST_ASIO_DECL win_iocp_handle_service(execution_context& context);
80 
81   // Destroy all user-defined handler objects owned by the service.
82   BOOST_ASIO_DECL void shutdown();
83 
84   // Construct a new handle implementation.
85   BOOST_ASIO_DECL void construct(implementation_type& impl);
86 
87   // Move-construct a new handle implementation.
88   BOOST_ASIO_DECL void move_construct(implementation_type& impl,
89       implementation_type& other_impl);
90 
91   // Move-assign from another handle implementation.
92   BOOST_ASIO_DECL void move_assign(implementation_type& impl,
93       win_iocp_handle_service& other_service,
94       implementation_type& other_impl);
95 
96   // Destroy a handle implementation.
97   BOOST_ASIO_DECL void destroy(implementation_type& impl);
98 
99   // Assign a native handle to a handle implementation.
100   BOOST_ASIO_DECL boost::system::error_code assign(implementation_type& impl,
101       const native_handle_type& handle, boost::system::error_code& ec);
102 
103   // Determine whether the handle is open.
is_open(const implementation_type & impl) const104   bool is_open(const implementation_type& impl) const
105   {
106     return impl.handle_ != INVALID_HANDLE_VALUE;
107   }
108 
109   // Destroy a handle implementation.
110   BOOST_ASIO_DECL boost::system::error_code close(implementation_type& impl,
111       boost::system::error_code& ec);
112 
113   // Get the native handle representation.
native_handle(const implementation_type & impl) const114   native_handle_type native_handle(const implementation_type& impl) const
115   {
116     return impl.handle_;
117   }
118 
119   // Cancel all operations associated with the handle.
120   BOOST_ASIO_DECL boost::system::error_code cancel(implementation_type& impl,
121       boost::system::error_code& ec);
122 
123   // Write the given data. Returns the number of bytes written.
124   template <typename ConstBufferSequence>
write_some(implementation_type & impl,const ConstBufferSequence & buffers,boost::system::error_code & ec)125   size_t write_some(implementation_type& impl,
126       const ConstBufferSequence& buffers, boost::system::error_code& ec)
127   {
128     return write_some_at(impl, 0, buffers, ec);
129   }
130 
131   // Write the given data at the specified offset. Returns the number of bytes
132   // written.
133   template <typename ConstBufferSequence>
write_some_at(implementation_type & impl,uint64_t offset,const ConstBufferSequence & buffers,boost::system::error_code & ec)134   size_t write_some_at(implementation_type& impl, uint64_t offset,
135       const ConstBufferSequence& buffers, boost::system::error_code& ec)
136   {
137     boost::asio::const_buffer buffer =
138       buffer_sequence_adapter<boost::asio::const_buffer,
139         ConstBufferSequence>::first(buffers);
140 
141     return do_write(impl, offset, buffer, ec);
142   }
143 
144   // Start an asynchronous write. The data being written must be valid for the
145   // lifetime of the asynchronous operation.
146   template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
async_write_some(implementation_type & impl,const ConstBufferSequence & buffers,Handler & handler,const IoExecutor & io_ex)147   void async_write_some(implementation_type& impl,
148       const ConstBufferSequence& buffers,
149       Handler& handler, const IoExecutor& io_ex)
150   {
151     // Allocate and construct an operation to wrap the handler.
152     typedef win_iocp_handle_write_op<
153         ConstBufferSequence, Handler, IoExecutor> op;
154     typename op::ptr p = { boost::asio::detail::addressof(handler),
155       op::ptr::allocate(handler), 0 };
156     p.p = new (p.v) op(buffers, handler, io_ex);
157 
158     BOOST_ASIO_HANDLER_CREATION((iocp_service_.context(), *p.p, "handle", &impl,
159           reinterpret_cast<uintmax_t>(impl.handle_), "async_write_some"));
160 
161     start_write_op(impl, 0,
162         buffer_sequence_adapter<boost::asio::const_buffer,
163           ConstBufferSequence>::first(buffers), p.p);
164     p.v = p.p = 0;
165   }
166 
167   // Start an asynchronous write at a specified offset. The data being written
168   // must be valid for the lifetime of the asynchronous operation.
169   template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
async_write_some_at(implementation_type & impl,uint64_t offset,const ConstBufferSequence & buffers,Handler & handler,const IoExecutor & io_ex)170   void async_write_some_at(implementation_type& impl,
171       uint64_t offset, const ConstBufferSequence& buffers,
172       Handler& handler, const IoExecutor& io_ex)
173   {
174     // Allocate and construct an operation to wrap the handler.
175     typedef win_iocp_handle_write_op<
176         ConstBufferSequence, Handler, IoExecutor> op;
177     typename op::ptr p = { boost::asio::detail::addressof(handler),
178       op::ptr::allocate(handler), 0 };
179     p.p = new (p.v) op(buffers, handler, io_ex);
180 
181     BOOST_ASIO_HANDLER_CREATION((iocp_service_.context(), *p.p, "handle", &impl,
182           reinterpret_cast<uintmax_t>(impl.handle_), "async_write_some_at"));
183 
184     start_write_op(impl, offset,
185         buffer_sequence_adapter<boost::asio::const_buffer,
186           ConstBufferSequence>::first(buffers), p.p);
187     p.v = p.p = 0;
188   }
189 
190   // Read some data. Returns the number of bytes received.
191   template <typename MutableBufferSequence>
read_some(implementation_type & impl,const MutableBufferSequence & buffers,boost::system::error_code & ec)192   size_t read_some(implementation_type& impl,
193       const MutableBufferSequence& buffers, boost::system::error_code& ec)
194   {
195     return read_some_at(impl, 0, buffers, ec);
196   }
197 
198   // Read some data at a specified offset. Returns the number of bytes received.
199   template <typename MutableBufferSequence>
read_some_at(implementation_type & impl,uint64_t offset,const MutableBufferSequence & buffers,boost::system::error_code & ec)200   size_t read_some_at(implementation_type& impl, uint64_t offset,
201       const MutableBufferSequence& buffers, boost::system::error_code& ec)
202   {
203     boost::asio::mutable_buffer buffer =
204       buffer_sequence_adapter<boost::asio::mutable_buffer,
205         MutableBufferSequence>::first(buffers);
206 
207     return do_read(impl, offset, buffer, ec);
208   }
209 
210   // Start an asynchronous read. The buffer for the data being received must be
211   // valid for the lifetime of the asynchronous operation.
212   template <typename MutableBufferSequence,
213       typename Handler, typename IoExecutor>
async_read_some(implementation_type & impl,const MutableBufferSequence & buffers,Handler & handler,const IoExecutor & io_ex)214   void async_read_some(implementation_type& impl,
215       const MutableBufferSequence& buffers,
216       Handler& handler, const IoExecutor& io_ex)
217   {
218     // Allocate and construct an operation to wrap the handler.
219     typedef win_iocp_handle_read_op<
220         MutableBufferSequence, Handler, IoExecutor> op;
221     typename op::ptr p = { boost::asio::detail::addressof(handler),
222       op::ptr::allocate(handler), 0 };
223     p.p = new (p.v) op(buffers, handler, io_ex);
224 
225     BOOST_ASIO_HANDLER_CREATION((iocp_service_.context(), *p.p, "handle", &impl,
226           reinterpret_cast<uintmax_t>(impl.handle_), "async_read_some"));
227 
228     start_read_op(impl, 0,
229         buffer_sequence_adapter<boost::asio::mutable_buffer,
230           MutableBufferSequence>::first(buffers), p.p);
231     p.v = p.p = 0;
232   }
233 
234   // Start an asynchronous read at a specified offset. The buffer for the data
235   // being received must be valid for the lifetime of the asynchronous
236   // operation.
237   template <typename MutableBufferSequence,
238       typename Handler, typename IoExecutor>
async_read_some_at(implementation_type & impl,uint64_t offset,const MutableBufferSequence & buffers,Handler & handler,const IoExecutor & io_ex)239   void async_read_some_at(implementation_type& impl,
240       uint64_t offset, const MutableBufferSequence& buffers,
241       Handler& handler, const IoExecutor& io_ex)
242   {
243     // Allocate and construct an operation to wrap the handler.
244     typedef win_iocp_handle_read_op<
245         MutableBufferSequence, Handler, IoExecutor> op;
246     typename op::ptr p = { boost::asio::detail::addressof(handler),
247       op::ptr::allocate(handler), 0 };
248     p.p = new (p.v) op(buffers, handler, io_ex);
249 
250     BOOST_ASIO_HANDLER_CREATION((iocp_service_.context(), *p.p, "handle", &impl,
251           reinterpret_cast<uintmax_t>(impl.handle_), "async_read_some_at"));
252 
253     start_read_op(impl, offset,
254         buffer_sequence_adapter<boost::asio::mutable_buffer,
255           MutableBufferSequence>::first(buffers), p.p);
256     p.v = p.p = 0;
257   }
258 
259 private:
260   // Prevent the use of the null_buffers type with this service.
261   size_t write_some(implementation_type& impl,
262       const null_buffers& buffers, boost::system::error_code& ec);
263   size_t write_some_at(implementation_type& impl, uint64_t offset,
264       const null_buffers& buffers, boost::system::error_code& ec);
265   template <typename Handler, typename IoExecutor>
266   void async_write_some(implementation_type& impl,
267       const null_buffers& buffers, Handler& handler,
268       const IoExecutor& io_ex);
269   template <typename Handler, typename IoExecutor>
270   void async_write_some_at(implementation_type& impl, uint64_t offset,
271       const null_buffers& buffers, Handler& handler, const IoExecutor& io_ex);
272   size_t read_some(implementation_type& impl,
273       const null_buffers& buffers, boost::system::error_code& ec);
274   size_t read_some_at(implementation_type& impl, uint64_t offset,
275       const null_buffers& buffers, boost::system::error_code& ec);
276   template <typename Handler, typename IoExecutor>
277   void async_read_some(implementation_type& impl,
278       const null_buffers& buffers, Handler& handler,
279       const IoExecutor& io_ex);
280   template <typename Handler, typename IoExecutor>
281   void async_read_some_at(implementation_type& impl, uint64_t offset,
282       const null_buffers& buffers, Handler& handler, const IoExecutor& io_ex);
283 
284   // Helper class for waiting for synchronous operations to complete.
285   class overlapped_wrapper;
286 
287   // Helper function to perform a synchronous write operation.
288   BOOST_ASIO_DECL size_t do_write(implementation_type& impl,
289       uint64_t offset, const boost::asio::const_buffer& buffer,
290       boost::system::error_code& ec);
291 
292   // Helper function to start a write operation.
293   BOOST_ASIO_DECL void start_write_op(implementation_type& impl,
294       uint64_t offset, const boost::asio::const_buffer& buffer,
295       operation* op);
296 
297   // Helper function to perform a synchronous write operation.
298   BOOST_ASIO_DECL size_t do_read(implementation_type& impl,
299       uint64_t offset, const boost::asio::mutable_buffer& buffer,
300       boost::system::error_code& ec);
301 
302   // Helper function to start a read operation.
303   BOOST_ASIO_DECL void start_read_op(implementation_type& impl,
304       uint64_t offset, const boost::asio::mutable_buffer& buffer,
305       operation* op);
306 
307   // Update the ID of the thread from which cancellation is safe.
308   BOOST_ASIO_DECL void update_cancellation_thread_id(implementation_type& impl);
309 
310   // Helper function to close a handle when the associated object is being
311   // destroyed.
312   BOOST_ASIO_DECL void close_for_destruction(implementation_type& impl);
313 
314   // The IOCP service used for running asynchronous operations and dispatching
315   // handlers.
316   win_iocp_io_context& iocp_service_;
317 
318   // Mutex to protect access to the linked list of implementations.
319   mutex mutex_;
320 
321   // The head of a linked list of all implementations.
322   implementation_type* impl_list_;
323 };
324 
325 } // namespace detail
326 } // namespace asio
327 } // namespace boost
328 
329 #include <boost/asio/detail/pop_options.hpp>
330 
331 #if defined(BOOST_ASIO_HEADER_ONLY)
332 # include <boost/asio/detail/impl/win_iocp_handle_service.ipp>
333 #endif // defined(BOOST_ASIO_HEADER_ONLY)
334 
335 #endif // defined(BOOST_ASIO_HAS_IOCP)
336 
337 #endif // BOOST_ASIO_DETAIL_WIN_IOCP_HANDLE_SERVICE_HPP
338