libstdc++
thread
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1 // <thread> -*- C++ -*-
2 
3 // Copyright (C) 2008-2014 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10 
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15 
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19 
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24 
25 /** @file include/thread
26  * This is a Standard C++ Library header.
27  */
28 
29 #ifndef _GLIBCXX_THREAD
30 #define _GLIBCXX_THREAD 1
31 
32 #pragma GCC system_header
33 
34 #if __cplusplus < 201103L
35 # include <bits/c++0x_warning.h>
36 #else
37 
38 #include <chrono>
39 #include <functional>
40 #include <memory>
41 #include <bits/functexcept.h>
42 #include <bits/functional_hash.h>
43 #include <bits/gthr.h>
44 
45 #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
46 
47 namespace std _GLIBCXX_VISIBILITY(default)
48 {
49 _GLIBCXX_BEGIN_NAMESPACE_VERSION
50 
51  /**
52  * @defgroup threads Threads
53  * @ingroup concurrency
54  *
55  * Classes for thread support.
56  * @{
57  */
58 
59  /// thread
60  class thread
61  {
62  public:
63  typedef __gthread_t native_handle_type;
64  struct _Impl_base;
66 
67  /// thread::id
68  class id
69  {
70  native_handle_type _M_thread;
71 
72  public:
73  id() noexcept : _M_thread() { }
74 
75  explicit
76  id(native_handle_type __id) : _M_thread(__id) { }
77 
78  private:
79  friend class thread;
80  friend class hash<thread::id>;
81 
82  friend bool
83  operator==(thread::id __x, thread::id __y) noexcept
84  { return __gthread_equal(__x._M_thread, __y._M_thread); }
85 
86  friend bool
87  operator<(thread::id __x, thread::id __y) noexcept
88  { return __x._M_thread < __y._M_thread; }
89 
90  template<class _CharT, class _Traits>
92  operator<<(basic_ostream<_CharT, _Traits>& __out, thread::id __id);
93  };
94 
95  // Simple base type that the templatized, derived class containing
96  // an arbitrary functor can be converted to and called.
97  struct _Impl_base
98  {
99  __shared_base_type _M_this_ptr;
100 
101  inline virtual ~_Impl_base();
102 
103  virtual void _M_run() = 0;
104  };
105 
106  template<typename _Callable>
107  struct _Impl : public _Impl_base
108  {
109  _Callable _M_func;
110 
111  _Impl(_Callable&& __f) : _M_func(std::forward<_Callable>(__f))
112  { }
113 
114  void
115  _M_run() { _M_func(); }
116  };
117 
118  private:
119  id _M_id;
120 
121  public:
122  thread() noexcept = default;
123  // _GLIBCXX_RESOLVE_LIB_DEFECTS
124  // 2097. packaged_task constructors should be constrained
125  thread(thread&) = delete;
126  thread(const thread&) = delete;
127 
128  thread(thread&& __t) noexcept
129  { swap(__t); }
130 
131  template<typename _Callable, typename... _Args>
132  explicit
133  thread(_Callable&& __f, _Args&&... __args)
134  {
135 #ifdef GTHR_ACTIVE_PROXY
136  __asm ("" : : "r" (&pthread_create));
137 #endif
138  _M_start_thread(_M_make_routine(std::__bind_simple(
139  std::forward<_Callable>(__f),
140  std::forward<_Args>(__args)...)));
141  }
142 
143  ~thread()
144  {
145  if (joinable())
146  std::terminate();
147  }
148 
149  thread& operator=(const thread&) = delete;
150 
151  thread& operator=(thread&& __t) noexcept
152  {
153  if (joinable())
154  std::terminate();
155  swap(__t);
156  return *this;
157  }
158 
159  void
160  swap(thread& __t) noexcept
161  { std::swap(_M_id, __t._M_id); }
162 
163  bool
164  joinable() const noexcept
165  { return !(_M_id == id()); }
166 
167  void
168  join();
169 
170  void
171  detach();
172 
173  thread::id
174  get_id() const noexcept
175  { return _M_id; }
176 
177  /** @pre thread is joinable
178  */
179  native_handle_type
181  { return _M_id._M_thread; }
182 
183  // Returns a value that hints at the number of hardware thread contexts.
184  static unsigned int
185  hardware_concurrency() noexcept;
186 
187  private:
188  void
189  _M_start_thread(__shared_base_type);
190 
191  template<typename _Callable>
192  shared_ptr<_Impl<_Callable>>
193  _M_make_routine(_Callable&& __f)
194  {
195  // Create and allocate full data structure, not base.
196  return std::make_shared<_Impl<_Callable>>(std::forward<_Callable>(__f));
197  }
198  };
199 
200  inline thread::_Impl_base::~_Impl_base() = default;
201 
202  inline void
203  swap(thread& __x, thread& __y) noexcept
204  { __x.swap(__y); }
205 
206  inline bool
207  operator!=(thread::id __x, thread::id __y) noexcept
208  { return !(__x == __y); }
209 
210  inline bool
211  operator<=(thread::id __x, thread::id __y) noexcept
212  { return !(__y < __x); }
213 
214  inline bool
215  operator>(thread::id __x, thread::id __y) noexcept
216  { return __y < __x; }
217 
218  inline bool
219  operator>=(thread::id __x, thread::id __y) noexcept
220  { return !(__x < __y); }
221 
222  // DR 889.
223  /// std::hash specialization for thread::id.
224  template<>
225  struct hash<thread::id>
226  : public __hash_base<size_t, thread::id>
227  {
228  size_t
229  operator()(const thread::id& __id) const noexcept
230  { return std::_Hash_impl::hash(__id._M_thread); }
231  };
232 
233  template<class _CharT, class _Traits>
235  operator<<(basic_ostream<_CharT, _Traits>& __out, thread::id __id)
236  {
237  if (__id == thread::id())
238  return __out << "thread::id of a non-executing thread";
239  else
240  return __out << __id._M_thread;
241  }
242 
243 _GLIBCXX_END_NAMESPACE_VERSION
244 
245  /** @namespace std::this_thread
246  * @brief ISO C++ 2011 entities sub-namespace for thread.
247  * 30.3.2 Namespace this_thread.
248  */
249  namespace this_thread
250  {
251  _GLIBCXX_BEGIN_NAMESPACE_VERSION
252 
253  /// get_id
254  inline thread::id
255  get_id() noexcept { return thread::id(__gthread_self()); }
256 
257  /// yield
258  inline void
259  yield() noexcept
260  {
261 #ifdef _GLIBCXX_USE_SCHED_YIELD
262  __gthread_yield();
263 #endif
264  }
265 
266  void
267  __sleep_for(chrono::seconds, chrono::nanoseconds);
268 
269  /// sleep_for
270  template<typename _Rep, typename _Period>
271  inline void
273  {
274  if (__rtime <= __rtime.zero())
275  return;
276  auto __s = chrono::duration_cast<chrono::seconds>(__rtime);
277  auto __ns = chrono::duration_cast<chrono::nanoseconds>(__rtime - __s);
278 #ifdef _GLIBCXX_USE_NANOSLEEP
279  __gthread_time_t __ts =
280  {
281  static_cast<std::time_t>(__s.count()),
282  static_cast<long>(__ns.count())
283  };
284  ::nanosleep(&__ts, 0);
285 #else
286  __sleep_for(__s, __ns);
287 #endif
288  }
289 
290  /// sleep_until
291  template<typename _Clock, typename _Duration>
292  inline void
294  {
295  auto __now = _Clock::now();
296  if (__now < __atime)
297  sleep_for(__atime - __now);
298  }
299 
300  _GLIBCXX_END_NAMESPACE_VERSION
301  }
302 
303  // @} group threads
304 
305 } // namespace
306 
307 #endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1
308 
309 #endif // C++11
310 
311 #endif // _GLIBCXX_THREAD
thread::id
Definition: thread:68
native_handle_type native_handle()
Definition: thread:180
Primary class template hash.
Definition: system_error:115
thread
Definition: thread:60
time_point
Definition: chrono:67
void sleep_until(const chrono::time_point< _Clock, _Duration > &__atime)
sleep_until
Definition: thread:293
void sleep_for(const chrono::duration< _Rep, _Period > &__rtime)
sleep_for
Definition: thread:272
thread::id get_id() noexcept
get_id
Definition: thread:255
void terminate() noexcept __attribute__((__noreturn__))
Template class basic_ostream.
Definition: iosfwd:86
constexpr enable_if< __is_duration< _ToDur >::value, _ToDur >::type duration_cast(const duration< _Rep, _Period > &__d)
duration_cast
Definition: chrono:194
duration
Definition: chrono:64
void yield() noexcept
yield
Definition: thread:259
constexpr _Tp && forward(typename std::remove_reference< _Tp >::type &__t) noexcept
Forward an lvalue.
Definition: move.h:76