2 //===--------------------------- thread -----------------------------------===//
4 // The LLVM Compiler Infrastructure
6 // This file is dual licensed under the MIT and the University of Illinois Open
7 // Source Licenses. See LICENSE.TXT for details.
9 //===----------------------------------------------------------------------===//
11 #ifndef _LIBCPP_THREAD
12 #define _LIBCPP_THREAD
18 #define __STDCPP_THREADS__ __cplusplus
27 typedef pthread_t native_handle_type;
30 template <class F, class ...Args> explicit thread(F&& f, Args&&... args);
33 thread(const thread&) = delete;
34 thread(thread&& t) noexcept;
36 thread& operator=(const thread&) = delete;
37 thread& operator=(thread&& t) noexcept;
39 void swap(thread& t) noexcept;
41 bool joinable() const noexcept;
44 id get_id() const noexcept;
45 native_handle_type native_handle();
47 static unsigned hardware_concurrency() noexcept;
50 void swap(thread& x, thread& y) noexcept;
58 bool operator==(thread::id x, thread::id y) noexcept;
59 bool operator!=(thread::id x, thread::id y) noexcept;
60 bool operator< (thread::id x, thread::id y) noexcept;
61 bool operator<=(thread::id x, thread::id y) noexcept;
62 bool operator> (thread::id x, thread::id y) noexcept;
63 bool operator>=(thread::id x, thread::id y) noexcept;
65 template<class charT, class traits>
66 basic_ostream<charT, traits>&
67 operator<<(basic_ostream<charT, traits>& out, thread::id id);
72 thread::id get_id() noexcept;
74 void yield() noexcept;
76 template <class Clock, class Duration>
77 void sleep_until(const chrono::time_point<Clock, Duration>& abs_time);
79 template <class Rep, class Period>
80 void sleep_for(const chrono::duration<Rep, Period>& rel_time);
90 #include <__functional_base>
91 #include <type_traits>
95 #include <system_error>
97 #include <__mutex_base>
98 #ifndef _LIBCPP_CXX03_LANG
101 #include <__threading_support>
104 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
105 #pragma GCC system_header
108 #define __STDCPP_THREADS__ __cplusplus
110 #ifdef _LIBCPP_HAS_NO_THREADS
111 #error <thread> is not supported on this single threaded system
112 #else // !_LIBCPP_HAS_NO_THREADS
114 _LIBCPP_BEGIN_NAMESPACE_STD
116 template <class _Tp> class __thread_specific_ptr;
117 class _LIBCPP_TYPE_VIS __thread_struct;
118 class _LIBCPP_HIDDEN __thread_struct_imp;
119 class __assoc_sub_state;
121 _LIBCPP_FUNC_VIS __thread_specific_ptr<__thread_struct>& __thread_local_data();
123 class _LIBCPP_TYPE_VIS __thread_struct
125 __thread_struct_imp* __p_;
127 __thread_struct(const __thread_struct&);
128 __thread_struct& operator=(const __thread_struct&);
133 void notify_all_at_thread_exit(condition_variable*, mutex*);
134 void __make_ready_at_thread_exit(__assoc_sub_state*);
138 class __thread_specific_ptr
140 __libcpp_tls_key __key_;
142 // Only __thread_local_data() may construct a __thread_specific_ptr
143 // and only with _Tp == __thread_struct.
144 static_assert((is_same<_Tp, __thread_struct>::value), "");
145 __thread_specific_ptr();
146 friend _LIBCPP_FUNC_VIS __thread_specific_ptr<__thread_struct>& __thread_local_data();
148 __thread_specific_ptr(const __thread_specific_ptr&);
149 __thread_specific_ptr& operator=(const __thread_specific_ptr&);
151 static void _LIBCPP_TLS_DESTRUCTOR_CC __at_thread_exit(void*);
154 typedef _Tp* pointer;
156 ~__thread_specific_ptr();
158 _LIBCPP_INLINE_VISIBILITY
159 pointer get() const {return static_cast<_Tp*>(__libcpp_tls_get(__key_));}
160 _LIBCPP_INLINE_VISIBILITY
161 pointer operator*() const {return *get();}
162 _LIBCPP_INLINE_VISIBILITY
163 pointer operator->() const {return get();}
164 void set_pointer(pointer __p);
168 void _LIBCPP_TLS_DESTRUCTOR_CC
169 __thread_specific_ptr<_Tp>::__at_thread_exit(void* __p)
171 delete static_cast<pointer>(__p);
175 __thread_specific_ptr<_Tp>::__thread_specific_ptr()
178 __libcpp_tls_create(&__key_, &__thread_specific_ptr::__at_thread_exit);
180 __throw_system_error(__ec, "__thread_specific_ptr construction failed");
184 __thread_specific_ptr<_Tp>::~__thread_specific_ptr()
186 // __thread_specific_ptr is only created with a static storage duration
187 // so this destructor is only invoked during program termination. Invoking
188 // pthread_key_delete(__key_) may prevent other threads from deleting their
189 // thread local data. For this reason we leak the key.
194 __thread_specific_ptr<_Tp>::set_pointer(pointer __p)
196 _LIBCPP_ASSERT(get() == nullptr,
197 "Attempting to overwrite thread local data");
198 __libcpp_tls_set(__key_, __p);
201 class _LIBCPP_TYPE_VIS thread;
202 class _LIBCPP_TYPE_VIS __thread_id;
204 namespace this_thread
207 _LIBCPP_INLINE_VISIBILITY __thread_id get_id() _NOEXCEPT;
211 template<> struct hash<__thread_id>;
213 class _LIBCPP_TEMPLATE_VIS __thread_id
215 // FIXME: pthread_t is a pointer on Darwin but a long on Linux.
216 // NULL is the no-thread value on Darwin. Someone needs to check
217 // on other platforms. We assume 0 works everywhere for now.
218 __libcpp_thread_id __id_;
221 _LIBCPP_INLINE_VISIBILITY
222 __thread_id() _NOEXCEPT : __id_(0) {}
224 friend _LIBCPP_INLINE_VISIBILITY
225 bool operator==(__thread_id __x, __thread_id __y) _NOEXCEPT
226 {return __libcpp_thread_id_equal(__x.__id_, __y.__id_);}
227 friend _LIBCPP_INLINE_VISIBILITY
228 bool operator!=(__thread_id __x, __thread_id __y) _NOEXCEPT
229 {return !(__x == __y);}
230 friend _LIBCPP_INLINE_VISIBILITY
231 bool operator< (__thread_id __x, __thread_id __y) _NOEXCEPT
232 {return __libcpp_thread_id_less(__x.__id_, __y.__id_);}
233 friend _LIBCPP_INLINE_VISIBILITY
234 bool operator<=(__thread_id __x, __thread_id __y) _NOEXCEPT
235 {return !(__y < __x);}
236 friend _LIBCPP_INLINE_VISIBILITY
237 bool operator> (__thread_id __x, __thread_id __y) _NOEXCEPT
239 friend _LIBCPP_INLINE_VISIBILITY
240 bool operator>=(__thread_id __x, __thread_id __y) _NOEXCEPT
241 {return !(__x < __y);}
243 template<class _CharT, class _Traits>
245 _LIBCPP_INLINE_VISIBILITY
246 basic_ostream<_CharT, _Traits>&
247 operator<<(basic_ostream<_CharT, _Traits>& __os, __thread_id __id)
248 {return __os << __id.__id_;}
251 _LIBCPP_INLINE_VISIBILITY
252 __thread_id(__libcpp_thread_id __id) : __id_(__id) {}
254 friend __thread_id this_thread::get_id() _NOEXCEPT;
255 friend class _LIBCPP_TYPE_VIS thread;
256 friend struct _LIBCPP_TEMPLATE_VIS hash<__thread_id>;
260 struct _LIBCPP_TEMPLATE_VIS hash<__thread_id>
261 : public unary_function<__thread_id, size_t>
263 _LIBCPP_INLINE_VISIBILITY
264 size_t operator()(__thread_id __v) const _NOEXCEPT
266 return hash<__libcpp_thread_id>()(__v.__id_);
270 namespace this_thread
273 inline _LIBCPP_INLINE_VISIBILITY
277 return __libcpp_thread_get_current_id();
282 class _LIBCPP_TYPE_VIS thread
284 __libcpp_thread_t __t_;
286 thread(const thread&);
287 thread& operator=(const thread&);
289 typedef __thread_id id;
290 typedef __libcpp_thread_t native_handle_type;
292 _LIBCPP_INLINE_VISIBILITY
293 thread() _NOEXCEPT : __t_(_LIBCPP_NULL_THREAD) {}
294 #ifndef _LIBCPP_CXX03_LANG
295 template <class _Fp, class ..._Args,
296 class = typename enable_if
298 !is_same<typename decay<_Fp>::type, thread>::value
301 _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
302 explicit thread(_Fp&& __f, _Args&&... __args);
303 #else // _LIBCPP_CXX03_LANG
305 _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
306 explicit thread(_Fp __f);
310 #ifndef _LIBCPP_CXX03_LANG
311 _LIBCPP_INLINE_VISIBILITY
312 thread(thread&& __t) _NOEXCEPT : __t_(__t.__t_) {__t.__t_ = _LIBCPP_NULL_THREAD;}
313 _LIBCPP_INLINE_VISIBILITY
314 thread& operator=(thread&& __t) _NOEXCEPT;
315 #endif // _LIBCPP_CXX03_LANG
317 _LIBCPP_INLINE_VISIBILITY
318 void swap(thread& __t) _NOEXCEPT {_VSTD::swap(__t_, __t.__t_);}
320 _LIBCPP_INLINE_VISIBILITY
321 bool joinable() const _NOEXCEPT {return !__libcpp_thread_isnull(&__t_);}
324 _LIBCPP_INLINE_VISIBILITY
325 id get_id() const _NOEXCEPT {return __libcpp_thread_get_id(&__t_);}
326 _LIBCPP_INLINE_VISIBILITY
327 native_handle_type native_handle() _NOEXCEPT {return __t_;}
329 static unsigned hardware_concurrency() _NOEXCEPT;
332 #ifndef _LIBCPP_CXX03_LANG
334 template <class _TSp, class _Fp, class ..._Args, size_t ..._Indices>
335 inline _LIBCPP_INLINE_VISIBILITY
337 __thread_execute(tuple<_TSp, _Fp, _Args...>& __t, __tuple_indices<_Indices...>)
339 __invoke(_VSTD::move(_VSTD::get<1>(__t)), _VSTD::move(_VSTD::get<_Indices>(__t))...);
343 void* __thread_proxy(void* __vp)
345 // _Fp = std::tuple< unique_ptr<__thread_struct>, Functor, Args...>
346 std::unique_ptr<_Fp> __p(static_cast<_Fp*>(__vp));
347 __thread_local_data().set_pointer(_VSTD::get<0>(*__p).release());
348 typedef typename __make_tuple_indices<tuple_size<_Fp>::value, 2>::type _Index;
349 __thread_execute(*__p, _Index());
353 template <class _Fp, class ..._Args,
356 thread::thread(_Fp&& __f, _Args&&... __args)
358 typedef unique_ptr<__thread_struct> _TSPtr;
359 _TSPtr __tsp(new __thread_struct);
360 typedef tuple<_TSPtr, typename decay<_Fp>::type, typename decay<_Args>::type...> _Gp;
361 _VSTD::unique_ptr<_Gp> __p(
362 new _Gp(std::move(__tsp),
363 __decay_copy(_VSTD::forward<_Fp>(__f)),
364 __decay_copy(_VSTD::forward<_Args>(__args))...));
365 int __ec = __libcpp_thread_create(&__t_, &__thread_proxy<_Gp>, __p.get());
369 __throw_system_error(__ec, "thread constructor failed");
374 thread::operator=(thread&& __t) _NOEXCEPT
376 if (!__libcpp_thread_isnull(&__t_))
379 __t.__t_ = _LIBCPP_NULL_THREAD;
383 #else // _LIBCPP_CXX03_LANG
386 struct __thread_invoke_pair {
387 // This type is used to pass memory for thread local storage and a functor
388 // to a newly created thread because std::pair doesn't work with
389 // std::unique_ptr in C++03.
390 __thread_invoke_pair(_Fp& __f) : __tsp_(new __thread_struct), __fn_(__f) {}
391 unique_ptr<__thread_struct> __tsp_;
396 void* __thread_proxy_cxx03(void* __vp)
398 std::unique_ptr<_Fp> __p(static_cast<_Fp*>(__vp));
399 __thread_local_data().set_pointer(__p->__tsp_.release());
405 thread::thread(_Fp __f)
408 typedef __thread_invoke_pair<_Fp> _InvokePair;
409 typedef std::unique_ptr<_InvokePair> _PairPtr;
410 _PairPtr __pp(new _InvokePair(__f));
411 int __ec = __libcpp_thread_create(&__t_, &__thread_proxy_cxx03<_InvokePair>, __pp.get());
415 __throw_system_error(__ec, "thread constructor failed");
418 #endif // _LIBCPP_CXX03_LANG
420 inline _LIBCPP_INLINE_VISIBILITY
421 void swap(thread& __x, thread& __y) _NOEXCEPT {__x.swap(__y);}
423 namespace this_thread
426 _LIBCPP_FUNC_VIS void sleep_for(const chrono::nanoseconds& __ns);
428 template <class _Rep, class _Period>
430 sleep_for(const chrono::duration<_Rep, _Period>& __d)
432 using namespace chrono;
433 if (__d > duration<_Rep, _Period>::zero())
435 _LIBCPP_CONSTEXPR duration<long double> _Max = nanoseconds::max();
439 __ns = duration_cast<nanoseconds>(__d);
444 __ns = nanoseconds::max();
449 template <class _Clock, class _Duration>
451 sleep_until(const chrono::time_point<_Clock, _Duration>& __t)
453 using namespace chrono;
455 condition_variable __cv;
456 unique_lock<mutex> __lk(__mut);
457 while (_Clock::now() < __t)
458 __cv.wait_until(__lk, __t);
461 template <class _Duration>
462 inline _LIBCPP_INLINE_VISIBILITY
464 sleep_until(const chrono::time_point<chrono::steady_clock, _Duration>& __t)
466 using namespace chrono;
467 sleep_for(__t - steady_clock::now());
470 inline _LIBCPP_INLINE_VISIBILITY
471 void yield() _NOEXCEPT {__libcpp_thread_yield();}
475 _LIBCPP_END_NAMESPACE_STD
477 #endif // !_LIBCPP_HAS_NO_THREADS
479 #endif // _LIBCPP_THREAD