1//
2// detail/deadline_timer_service.hpp
3// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4//
5// Copyright (c) 2003-2015 Christopher M. Kohlhoff (chris at kohlhoff dot com)
6//
7// Distributed under the Boost Software License, Version 1.0. (See accompanying
8// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
9//
10
11#ifndef BOOST_ASIO_DETAIL_DEADLINE_TIMER_SERVICE_HPP
12#define BOOST_ASIO_DETAIL_DEADLINE_TIMER_SERVICE_HPP
13
14#if defined(_MSC_VER) && (_MSC_VER >= 1200)
15# pragma once
16#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
17
18#include <boost/asio/detail/config.hpp>
19#include <cstddef>
20#include <boost/asio/error.hpp>
21#include <boost/asio/io_service.hpp>
22#include <boost/asio/detail/addressof.hpp>
23#include <boost/asio/detail/bind_handler.hpp>
24#include <boost/asio/detail/fenced_block.hpp>
25#include <boost/asio/detail/noncopyable.hpp>
26#include <boost/asio/detail/socket_ops.hpp>
27#include <boost/asio/detail/socket_types.hpp>
28#include <boost/asio/detail/timer_queue.hpp>
29#include <boost/asio/detail/timer_scheduler.hpp>
30#include <boost/asio/detail/wait_handler.hpp>
31#include <boost/asio/detail/wait_op.hpp>
32
33#if defined(BOOST_ASIO_WINDOWS_RUNTIME)
34# include <chrono>
35# include <thread>
36#endif // defined(BOOST_ASIO_WINDOWS_RUNTIME)
37
38#include <boost/asio/detail/push_options.hpp>
39
40namespace boost {
41namespace asio {
42namespace detail {
43
44template <typename Time_Traits>
45class deadline_timer_service
46{
47public:
48 // The time type.
49 typedef typename Time_Traits::time_type time_type;
50
51 // The duration type.
52 typedef typename Time_Traits::duration_type duration_type;
53
54 // The implementation type of the timer. This type is dependent on the
55 // underlying implementation of the timer service.
56 struct implementation_type
57 : private boost::asio::detail::noncopyable
58 {
59 time_type expiry;
60 bool might_have_pending_waits;
61 typename timer_queue<Time_Traits>::per_timer_data timer_data;
62 };
63
64 // Constructor.
65 deadline_timer_service(boost::asio::io_service& io_service)
66 : scheduler_(boost::asio::use_service<timer_scheduler>(io_service))
67 {
68 scheduler_.init_task();
69 scheduler_.add_timer_queue(timer_queue_);
70 }
71
72 // Destructor.
73 ~deadline_timer_service()
74 {
75 scheduler_.remove_timer_queue(timer_queue_);
76 }
77
78 // Destroy all user-defined handler objects owned by the service.
79 void shutdown_service()
80 {
81 }
82
83 // Construct a new timer implementation.
84 void construct(implementation_type& impl)
85 {
86 impl.expiry = time_type();
87 impl.might_have_pending_waits = false;
88 }
89
90 // Destroy a timer implementation.
91 void destroy(implementation_type& impl)
92 {
93 boost::system::error_code ec;
94 cancel(impl, ec);
95 }
96
97 // Cancel any asynchronous wait operations associated with the timer.
98 std::size_t cancel(implementation_type& impl, boost::system::error_code& ec)
99 {
100 if (!impl.might_have_pending_waits)
101 {
102 ec = boost::system::error_code();
103 return 0;
104 }
105
106 BOOST_ASIO_HANDLER_OPERATION(("deadline_timer", &impl, "cancel"));
107
108 std::size_t count = scheduler_.cancel_timer(timer_queue_, impl.timer_data);
109 impl.might_have_pending_waits = false;
110 ec = boost::system::error_code();
111 return count;
112 }
113
114 // Cancels one asynchronous wait operation associated with the timer.
115 std::size_t cancel_one(implementation_type& impl,
116 boost::system::error_code& ec)
117 {
118 if (!impl.might_have_pending_waits)
119 {
120 ec = boost::system::error_code();
121 return 0;
122 }
123
124 BOOST_ASIO_HANDLER_OPERATION(("deadline_timer", &impl, "cancel_one"));
125
126 std::size_t count = scheduler_.cancel_timer(
127 timer_queue_, impl.timer_data, 1);
128 if (count == 0)
129 impl.might_have_pending_waits = false;
130 ec = boost::system::error_code();
131 return count;
132 }
133
134 // Get the expiry time for the timer as an absolute time.
135 time_type expires_at(const implementation_type& impl) const
136 {
137 return impl.expiry;
138 }
139
140 // Set the expiry time for the timer as an absolute time.
141 std::size_t expires_at(implementation_type& impl,
142 const time_type& expiry_time, boost::system::error_code& ec)
143 {
144 std::size_t count = cancel(impl, ec);
145 impl.expiry = expiry_time;
146 ec = boost::system::error_code();
147 return count;
148 }
149
150 // Get the expiry time for the timer relative to now.
151 duration_type expires_from_now(const implementation_type& impl) const
152 {
153 return Time_Traits::subtract(expires_at(impl), Time_Traits::now());
154 }
155
156 // Set the expiry time for the timer relative to now.
157 std::size_t expires_from_now(implementation_type& impl,
158 const duration_type& expiry_time, boost::system::error_code& ec)
159 {
160 return expires_at(impl,
161 Time_Traits::add(Time_Traits::now(), expiry_time), ec);
162 }
163
164 // Perform a blocking wait on the timer.
165 void wait(implementation_type& impl, boost::system::error_code& ec)
166 {
167 time_type now = Time_Traits::now();
168 ec = boost::system::error_code();
169 while (Time_Traits::less_than(now, impl.expiry) && !ec)
170 {
171 this->do_wait(Time_Traits::to_posix_duration(
172 Time_Traits::subtract(impl.expiry, now)), ec);
173 now = Time_Traits::now();
174 }
175 }
176
177 // Start an asynchronous wait on the timer.
178 template <typename Handler>
179 void async_wait(implementation_type& impl, Handler& handler)
180 {
181 // Allocate and construct an operation to wrap the handler.
182 typedef wait_handler<Handler> op;
183 typename op::ptr p = { boost::asio::detail::addressof(handler),
184 boost_asio_handler_alloc_helpers::allocate(
185 sizeof(op), handler), 0 };
186 p.p = new (p.v) op(handler);
187
188 impl.might_have_pending_waits = true;
189
190 BOOST_ASIO_HANDLER_CREATION((p.p, "deadline_timer", &impl, "async_wait"));
191
192 scheduler_.schedule_timer(timer_queue_, impl.expiry, impl.timer_data, p.p);
193 p.v = p.p = 0;
194 }
195
196private:
197 // Helper function to wait given a duration type. The duration type should
198 // either be of type boost::posix_time::time_duration, or implement the
199 // required subset of its interface.
200 template <typename Duration>
201 void do_wait(const Duration& timeout, boost::system::error_code& ec)
202 {
203#if defined(BOOST_ASIO_WINDOWS_RUNTIME)
204 std::this_thread::sleep_for(
205 std::chrono::seconds(timeout.total_seconds())
206 + std::chrono::microseconds(timeout.total_microseconds()));
207 ec = boost::system::error_code();
208#else // defined(BOOST_ASIO_WINDOWS_RUNTIME)
209 ::timeval tv;
210 tv.tv_sec = timeout.total_seconds();
211 tv.tv_usec = timeout.total_microseconds() % 1000000;
212 socket_ops::select(0, 0, 0, 0, &tv, ec);
213#endif // defined(BOOST_ASIO_WINDOWS_RUNTIME)
214 }
215
216 // The queue of timers.
217 timer_queue<Time_Traits> timer_queue_;
218
219 // The object that schedules and executes timers. Usually a reactor.
220 timer_scheduler& scheduler_;
221};
222
223} // namespace detail
224} // namespace asio
225} // namespace boost
226
227#include <boost/asio/detail/pop_options.hpp>
228
229#endif // BOOST_ASIO_DETAIL_DEADLINE_TIMER_SERVICE_HPP
230