libstdc++
thread
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1 // <thread> -*- C++ -*-
2 
3 // Copyright (C) 2008, 2009, 2010, 2011 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 #ifndef __GXX_EXPERIMENTAL_CXX0X__
35 # include <bits/c++0x_warning.h>
36 #else
37 
38 #include <chrono>
39 #include <functional>
40 #include <memory>
41 #include <mutex>
42 #include <condition_variable>
43 #include <bits/functexcept.h>
44 #include <bits/functional_hash.h>
45 #include <bits/gthr.h>
46 
47 #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
48 
49 namespace std _GLIBCXX_VISIBILITY(default)
50 {
51 _GLIBCXX_BEGIN_NAMESPACE_VERSION
52 
53  /**
54  * @defgroup threads Threads
55  * @ingroup concurrency
56  *
57  * Classes for thread support.
58  * @{
59  */
60 
61  /// thread
62  class thread
63  {
64  public:
65  typedef __gthread_t native_handle_type;
66  struct _Impl_base;
68 
69  /// thread::id
70  class id
71  {
72  native_handle_type _M_thread;
73 
74  public:
75  id() : _M_thread() { }
76 
77  explicit
78  id(native_handle_type __id) : _M_thread(__id) { }
79 
80  private:
81  friend class thread;
82  friend class hash<thread::id>;
83 
84  friend bool
85  operator==(thread::id __x, thread::id __y)
86  { return __gthread_equal(__x._M_thread, __y._M_thread); }
87 
88  friend bool
89  operator<(thread::id __x, thread::id __y)
90  { return __x._M_thread < __y._M_thread; }
91 
92  template<class _CharT, class _Traits>
94  operator<<(basic_ostream<_CharT, _Traits>& __out, thread::id __id);
95  };
96 
97  // Simple base type that the templatized, derived class containing
98  // an arbitrary functor can be converted to and called.
99  struct _Impl_base
100  {
101  __shared_base_type _M_this_ptr;
102 
103  inline virtual ~_Impl_base();
104 
105  virtual void _M_run() = 0;
106  };
107 
108  template<typename _Callable>
109  struct _Impl : public _Impl_base
110  {
111  _Callable _M_func;
112 
113  _Impl(_Callable&& __f) : _M_func(std::forward<_Callable>(__f))
114  { }
115 
116  void
117  _M_run() { _M_func(); }
118  };
119 
120  private:
121  id _M_id;
122 
123  public:
124  thread() = default;
125  thread(thread&) = delete;
126  thread(const thread&) = delete;
127 
128  thread(thread&& __t)
129  { swap(__t); }
130 
131  template<typename _Callable, typename... _Args>
132  explicit
133  thread(_Callable&& __f, _Args&&... __args)
134  {
135  _M_start_thread(_M_make_routine(std::bind<void>(
136  std::forward<_Callable>(__f),
137  std::forward<_Args>(__args)...)));
138  }
139 
140  ~thread()
141  {
142  if (joinable())
143  std::terminate();
144  }
145 
146  thread& operator=(const thread&) = delete;
147 
148  thread& operator=(thread&& __t)
149  {
150  if (joinable())
151  std::terminate();
152  swap(__t);
153  return *this;
154  }
155 
156  void
157  swap(thread& __t)
158  { std::swap(_M_id, __t._M_id); }
159 
160  bool
161  joinable() const
162  { return !(_M_id == id()); }
163 
164  void
165  join();
166 
167  void
168  detach();
169 
170  thread::id
171  get_id() const
172  { return _M_id; }
173 
174  /** @pre thread is joinable
175  */
176  native_handle_type
178  { return _M_id._M_thread; }
179 
180  // Returns a value that hints at the number of hardware thread contexts.
181  static unsigned int
182  hardware_concurrency()
183  { return 0; }
184 
185  private:
186  void
187  _M_start_thread(__shared_base_type);
188 
189  template<typename _Callable>
190  shared_ptr<_Impl<_Callable>>
191  _M_make_routine(_Callable&& __f)
192  {
193  // Create and allocate full data structure, not base.
194  return make_shared<_Impl<_Callable>>(std::forward<_Callable>(__f));
195  }
196  };
197 
198  inline thread::_Impl_base::~_Impl_base() = default;
199 
200  inline void
201  swap(thread& __x, thread& __y)
202  { __x.swap(__y); }
203 
204  inline bool
205  operator!=(thread::id __x, thread::id __y)
206  { return !(__x == __y); }
207 
208  inline bool
209  operator<=(thread::id __x, thread::id __y)
210  { return !(__y < __x); }
211 
212  inline bool
213  operator>(thread::id __x, thread::id __y)
214  { return __y < __x; }
215 
216  inline bool
217  operator>=(thread::id __x, thread::id __y)
218  { return !(__x < __y); }
219 
220  // DR 889.
221  /// std::hash specialization for thread::id.
222  template<>
223  struct hash<thread::id>
224  : public __hash_base<size_t, thread::id>
225  {
226  size_t
227  operator()(const thread::id& __id) const
228  { return std::_Hash_impl::hash(__id._M_thread); }
229  };
230 
231  template<class _CharT, class _Traits>
233  operator<<(basic_ostream<_CharT, _Traits>& __out, thread::id __id)
234  {
235  if (__id == thread::id())
236  return __out << "thread::id of a non-executing thread";
237  else
238  return __out << __id._M_thread;
239  }
240 
241 _GLIBCXX_END_NAMESPACE_VERSION
242 
243  /** @namespace std::this_thread
244  * @brief ISO C++ 0x entities sub namespace for thread.
245  * 30.2.2 Namespace this_thread.
246  */
247  namespace this_thread
248  {
249  _GLIBCXX_BEGIN_NAMESPACE_VERSION
250 
251  /// get_id
252  inline thread::id
253  get_id() { return thread::id(__gthread_self()); }
254 
255 #ifdef _GLIBCXX_USE_SCHED_YIELD
256  /// yield
257  inline void
259  { __gthread_yield(); }
260 #endif
261 
262 #ifdef _GLIBCXX_USE_NANOSLEEP
263  /// sleep_until
264  template<typename _Clock, typename _Duration>
265  inline void
267  { sleep_for(__atime - _Clock::now()); }
268 
269  /// sleep_for
270  template<typename _Rep, typename _Period>
271  inline void
273  {
274  chrono::seconds __s =
276 
277  chrono::nanoseconds __ns =
279 
280  __gthread_time_t __ts =
281  {
282  static_cast<std::time_t>(__s.count()),
283  static_cast<long>(__ns.count())
284  };
285 
286  ::nanosleep(&__ts, 0);
287  }
288 #endif
289 
290  _GLIBCXX_END_NAMESPACE_VERSION
291  }
292 
293  // @} group threads
294 
295 } // namespace
296 
297 #endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1
298 
299 #endif // __GXX_EXPERIMENTAL_CXX0X__
300 
301 #endif // _GLIBCXX_THREAD