1 // Copyright (C) 2013,2014 Vicente J. Botet Escriba
2 //
3 //  Distributed under the Boost Software License, Version 1.0. (See accompanying
4 //  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
5 //
6 // 2013/09 Vicente J. Botet Escriba
7 //    Adapt to boost from CCIA C++11 implementation
8 
9 #ifndef BOOST_THREAD_EXECUTORS_EXECUTOR_HPP
10 #define BOOST_THREAD_EXECUTORS_EXECUTOR_HPP
11 
12 #include <boost/thread/detail/config.hpp>
13 #if defined BOOST_THREAD_PROVIDES_FUTURE_CONTINUATION && defined BOOST_THREAD_PROVIDES_EXECUTORS && defined BOOST_THREAD_USES_MOVE
14 
15 #include <boost/thread/detail/delete.hpp>
16 #include <boost/thread/detail/move.hpp>
17 #include <boost/thread/executors/work.hpp>
18 
19 #include <boost/config/abi_prefix.hpp>
20 
21 namespace boost
22 {
23   namespace executors
24   {
25   class executor
26   {
27   public:
28     /// type-erasure to store the works to do
29     typedef  executors::work work;
30 
31     /// executor is not copyable.
32     BOOST_THREAD_NO_COPYABLE(executor)
executor()33     executor() {}
34 
35     /**
36      * \par Effects
37      * Destroys the executor.
38      *
39      * \par Synchronization
40      * The completion of all the closures happen before the completion of the executor destructor.
41      */
~executor()42     virtual ~executor() {}
43 
44     /**
45      * \par Effects
46      * Close the \c executor for submissions.
47      * The worker threads will work until there is no more closures to run.
48      */
49     virtual void close() = 0;
50 
51     /**
52      * \par Returns
53      * Whether the pool is closed for submissions.
54      */
55     virtual bool closed() = 0;
56 
57     /**
58      * \par Effects
59      * The specified closure will be scheduled for execution at some point in the future.
60      * If invoked closure throws an exception the executor will call std::terminate, as is the case with threads.
61      *
62      * \par Synchronization
63      * Ccompletion of closure on a particular thread happens before destruction of thread's thread local variables.
64      *
65      * \par Throws
66      * \c sync_queue_is_closed if the thread pool is closed.
67      * Whatever exception that can be throw while storing the closure.
68      */
69     virtual void submit(BOOST_THREAD_RV_REF(work) closure) = 0;
70 //    virtual void submit(work& closure) = 0;
71 
72     /**
73      * \par Requires
74      * \c Closure is a model of Callable(void()) and a model of CopyConstructible/MoveConstructible.
75      *
76      * \par Effects
77      * The specified closure will be scheduled for execution at some point in the future.
78      * If invoked closure throws an exception the thread pool will call std::terminate, as is the case with threads.
79      *
80      * \par Synchronization
81      * Completion of closure on a particular thread happens before destruction of thread's thread local variables.
82      *
83      * \par Throws
84      * \c sync_queue_is_closed if the thread pool is closed.
85      * Whatever exception that can be throw while storing the closure.
86      */
87 
88 #if defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
89     template <typename Closure>
submit(Closure & closure)90     void submit(Closure & closure)
91     {
92       work w ((closure));
93       submit(boost::move(w));
94     }
95 #endif
submit(void (* closure)())96     void submit(void (*closure)())
97     {
98       work w ((closure));
99       submit(boost::move(w));
100     }
101 
102     template <typename Closure>
submit(BOOST_THREAD_FWD_REF (Closure)closure)103     void submit(BOOST_THREAD_FWD_REF(Closure) closure)
104     {
105       //submit(work(boost::forward<Closure>(closure)));
106       work w((boost::forward<Closure>(closure)));
107       submit(boost::move(w));
108     }
109 
110     /**
111      * \par Effects
112      * Try to execute one task.
113      *
114      * \par Returns
115      * Whether a task has been executed.
116      *
117      * \par Throws
118      * Whatever the current task constructor throws or the task() throws.
119      */
120     virtual bool try_executing_one() = 0;
121 
122     /**
123      * \par Requires
124      * This must be called from an scheduled task.
125      *
126      * \par Effects
127      * Reschedule functions until pred()
128      */
129     template <typename Pred>
reschedule_until(Pred const & pred)130     bool reschedule_until(Pred const& pred)
131     {
132       do {
133         //schedule_one_or_yield();
134         if ( ! try_executing_one())
135         {
136           return false;
137         }
138       } while (! pred());
139       return true;
140     }
141   };
142 
143   }
144   using executors::executor;
145 }
146 
147 #include <boost/config/abi_suffix.hpp>
148 
149 #endif
150 #endif
151