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
109 #include <__undef_macros>
111 #define __STDCPP_THREADS__ __cplusplus
113 #ifdef _LIBCPP_HAS_NO_THREADS
114 #error <thread> is not supported on this single threaded system
115 #else // !_LIBCPP_HAS_NO_THREADS
117 _LIBCPP_BEGIN_NAMESPACE_STD
119 template <class _Tp> class __thread_specific_ptr;
120 class _LIBCPP_TYPE_VIS __thread_struct;
121 class _LIBCPP_HIDDEN __thread_struct_imp;
122 class __assoc_sub_state;
124 _LIBCPP_FUNC_VIS __thread_specific_ptr<__thread_struct>& __thread_local_data();
126 class _LIBCPP_TYPE_VIS __thread_struct
128 __thread_struct_imp* __p_;
130 __thread_struct(const __thread_struct&);
131 __thread_struct& operator=(const __thread_struct&);
136 void notify_all_at_thread_exit(condition_variable*, mutex*);
137 void __make_ready_at_thread_exit(__assoc_sub_state*);
141 class __thread_specific_ptr
143 __libcpp_tls_key __key_;
145 // Only __thread_local_data() may construct a __thread_specific_ptr
146 // and only with _Tp == __thread_struct.
147 static_assert((is_same<_Tp, __thread_struct>::value), "");
148 __thread_specific_ptr();
149 friend _LIBCPP_FUNC_VIS __thread_specific_ptr<__thread_struct>& __thread_local_data();
151 __thread_specific_ptr(const __thread_specific_ptr&);
152 __thread_specific_ptr& operator=(const __thread_specific_ptr&);
154 static void _LIBCPP_TLS_DESTRUCTOR_CC __at_thread_exit(void*);
157 typedef _Tp* pointer;
159 ~__thread_specific_ptr();
161 _LIBCPP_INLINE_VISIBILITY
162 pointer get() const {return static_cast<_Tp*>(__libcpp_tls_get(__key_));}
163 _LIBCPP_INLINE_VISIBILITY
164 pointer operator*() const {return *get();}
165 _LIBCPP_INLINE_VISIBILITY
166 pointer operator->() const {return get();}
167 void set_pointer(pointer __p);
171 void _LIBCPP_TLS_DESTRUCTOR_CC
172 __thread_specific_ptr<_Tp>::__at_thread_exit(void* __p)
174 delete static_cast<pointer>(__p);
178 __thread_specific_ptr<_Tp>::__thread_specific_ptr()
181 __libcpp_tls_create(&__key_, &__thread_specific_ptr::__at_thread_exit);
183 __throw_system_error(__ec, "__thread_specific_ptr construction failed");
187 __thread_specific_ptr<_Tp>::~__thread_specific_ptr()
189 // __thread_specific_ptr is only created with a static storage duration
190 // so this destructor is only invoked during program termination. Invoking
191 // pthread_key_delete(__key_) may prevent other threads from deleting their
192 // thread local data. For this reason we leak the key.
197 __thread_specific_ptr<_Tp>::set_pointer(pointer __p)
199 _LIBCPP_ASSERT(get() == nullptr,
200 "Attempting to overwrite thread local data");
201 __libcpp_tls_set(__key_, __p);
204 class _LIBCPP_TYPE_VIS thread;
205 class _LIBCPP_TYPE_VIS __thread_id;
207 namespace this_thread
210 _LIBCPP_INLINE_VISIBILITY __thread_id get_id() _NOEXCEPT;
214 template<> struct hash<__thread_id>;
216 class _LIBCPP_TEMPLATE_VIS __thread_id
218 // FIXME: pthread_t is a pointer on Darwin but a long on Linux.
219 // NULL is the no-thread value on Darwin. Someone needs to check
220 // on other platforms. We assume 0 works everywhere for now.
221 __libcpp_thread_id __id_;
224 _LIBCPP_INLINE_VISIBILITY
225 __thread_id() _NOEXCEPT : __id_(0) {}
227 friend _LIBCPP_INLINE_VISIBILITY
228 bool operator==(__thread_id __x, __thread_id __y) _NOEXCEPT
229 {return __libcpp_thread_id_equal(__x.__id_, __y.__id_);}
230 friend _LIBCPP_INLINE_VISIBILITY
231 bool operator!=(__thread_id __x, __thread_id __y) _NOEXCEPT
232 {return !(__x == __y);}
233 friend _LIBCPP_INLINE_VISIBILITY
234 bool operator< (__thread_id __x, __thread_id __y) _NOEXCEPT
235 {return __libcpp_thread_id_less(__x.__id_, __y.__id_);}
236 friend _LIBCPP_INLINE_VISIBILITY
237 bool operator<=(__thread_id __x, __thread_id __y) _NOEXCEPT
238 {return !(__y < __x);}
239 friend _LIBCPP_INLINE_VISIBILITY
240 bool operator> (__thread_id __x, __thread_id __y) _NOEXCEPT
242 friend _LIBCPP_INLINE_VISIBILITY
243 bool operator>=(__thread_id __x, __thread_id __y) _NOEXCEPT
244 {return !(__x < __y);}
246 template<class _CharT, class _Traits>
248 _LIBCPP_INLINE_VISIBILITY
249 basic_ostream<_CharT, _Traits>&
250 operator<<(basic_ostream<_CharT, _Traits>& __os, __thread_id __id)
251 {return __os << __id.__id_;}
254 _LIBCPP_INLINE_VISIBILITY
255 __thread_id(__libcpp_thread_id __id) : __id_(__id) {}
257 friend __thread_id this_thread::get_id() _NOEXCEPT;
258 friend class _LIBCPP_TYPE_VIS thread;
259 friend struct _LIBCPP_TEMPLATE_VIS hash<__thread_id>;
263 struct _LIBCPP_TEMPLATE_VIS hash<__thread_id>
264 : public unary_function<__thread_id, size_t>
266 _LIBCPP_INLINE_VISIBILITY
267 size_t operator()(__thread_id __v) const _NOEXCEPT
269 return hash<__libcpp_thread_id>()(__v.__id_);
273 namespace this_thread
276 inline _LIBCPP_INLINE_VISIBILITY
280 return __libcpp_thread_get_current_id();
285 class _LIBCPP_TYPE_VIS thread
287 __libcpp_thread_t __t_;
289 thread(const thread&);
290 thread& operator=(const thread&);
292 typedef __thread_id id;
293 typedef __libcpp_thread_t native_handle_type;
295 _LIBCPP_INLINE_VISIBILITY
296 thread() _NOEXCEPT : __t_(_LIBCPP_NULL_THREAD) {}
297 #ifndef _LIBCPP_CXX03_LANG
298 template <class _Fp, class ..._Args,
299 class = typename enable_if
301 !is_same<typename __uncvref<_Fp>::type, thread>::value
304 _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
305 explicit thread(_Fp&& __f, _Args&&... __args);
306 #else // _LIBCPP_CXX03_LANG
308 _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
309 explicit thread(_Fp __f);
313 #ifndef _LIBCPP_CXX03_LANG
314 _LIBCPP_INLINE_VISIBILITY
315 thread(thread&& __t) _NOEXCEPT : __t_(__t.__t_) {__t.__t_ = _LIBCPP_NULL_THREAD;}
316 _LIBCPP_INLINE_VISIBILITY
317 thread& operator=(thread&& __t) _NOEXCEPT;
318 #endif // _LIBCPP_CXX03_LANG
320 _LIBCPP_INLINE_VISIBILITY
321 void swap(thread& __t) _NOEXCEPT {_VSTD::swap(__t_, __t.__t_);}
323 _LIBCPP_INLINE_VISIBILITY
324 bool joinable() const _NOEXCEPT {return !__libcpp_thread_isnull(&__t_);}
327 _LIBCPP_INLINE_VISIBILITY
328 id get_id() const _NOEXCEPT {return __libcpp_thread_get_id(&__t_);}
329 _LIBCPP_INLINE_VISIBILITY
330 native_handle_type native_handle() _NOEXCEPT {return __t_;}
332 static unsigned hardware_concurrency() _NOEXCEPT;
335 #ifndef _LIBCPP_CXX03_LANG
337 template <class _TSp, class _Fp, class ..._Args, size_t ..._Indices>
338 inline _LIBCPP_INLINE_VISIBILITY
340 __thread_execute(tuple<_TSp, _Fp, _Args...>& __t, __tuple_indices<_Indices...>)
342 __invoke(_VSTD::move(_VSTD::get<1>(__t)), _VSTD::move(_VSTD::get<_Indices>(__t))...);
346 void* __thread_proxy(void* __vp)
348 // _Fp = std::tuple< unique_ptr<__thread_struct>, Functor, Args...>
349 std::unique_ptr<_Fp> __p(static_cast<_Fp*>(__vp));
350 __thread_local_data().set_pointer(_VSTD::get<0>(*__p).release());
351 typedef typename __make_tuple_indices<tuple_size<_Fp>::value, 2>::type _Index;
352 __thread_execute(*__p, _Index());
356 template <class _Fp, class ..._Args,
359 thread::thread(_Fp&& __f, _Args&&... __args)
361 typedef unique_ptr<__thread_struct> _TSPtr;
362 _TSPtr __tsp(new __thread_struct);
363 typedef tuple<_TSPtr, typename decay<_Fp>::type, typename decay<_Args>::type...> _Gp;
364 _VSTD::unique_ptr<_Gp> __p(
365 new _Gp(std::move(__tsp),
366 __decay_copy(_VSTD::forward<_Fp>(__f)),
367 __decay_copy(_VSTD::forward<_Args>(__args))...));
368 int __ec = __libcpp_thread_create(&__t_, &__thread_proxy<_Gp>, __p.get());
372 __throw_system_error(__ec, "thread constructor failed");
377 thread::operator=(thread&& __t) _NOEXCEPT
379 if (!__libcpp_thread_isnull(&__t_))
382 __t.__t_ = _LIBCPP_NULL_THREAD;
386 #else // _LIBCPP_CXX03_LANG
389 struct __thread_invoke_pair {
390 // This type is used to pass memory for thread local storage and a functor
391 // to a newly created thread because std::pair doesn't work with
392 // std::unique_ptr in C++03.
393 __thread_invoke_pair(_Fp& __f) : __tsp_(new __thread_struct), __fn_(__f) {}
394 unique_ptr<__thread_struct> __tsp_;
399 void* __thread_proxy_cxx03(void* __vp)
401 std::unique_ptr<_Fp> __p(static_cast<_Fp*>(__vp));
402 __thread_local_data().set_pointer(__p->__tsp_.release());
408 thread::thread(_Fp __f)
411 typedef __thread_invoke_pair<_Fp> _InvokePair;
412 typedef std::unique_ptr<_InvokePair> _PairPtr;
413 _PairPtr __pp(new _InvokePair(__f));
414 int __ec = __libcpp_thread_create(&__t_, &__thread_proxy_cxx03<_InvokePair>, __pp.get());
418 __throw_system_error(__ec, "thread constructor failed");
421 #endif // _LIBCPP_CXX03_LANG
423 inline _LIBCPP_INLINE_VISIBILITY
424 void swap(thread& __x, thread& __y) _NOEXCEPT {__x.swap(__y);}
426 namespace this_thread
429 _LIBCPP_FUNC_VIS void sleep_for(const chrono::nanoseconds& __ns);
431 template <class _Rep, class _Period>
433 sleep_for(const chrono::duration<_Rep, _Period>& __d)
435 using namespace chrono;
436 if (__d > duration<_Rep, _Period>::zero())
438 _LIBCPP_CONSTEXPR duration<long double> _Max = nanoseconds::max();
442 __ns = duration_cast<nanoseconds>(__d);
447 __ns = nanoseconds::max();
452 template <class _Clock, class _Duration>
454 sleep_until(const chrono::time_point<_Clock, _Duration>& __t)
456 using namespace chrono;
458 condition_variable __cv;
459 unique_lock<mutex> __lk(__mut);
460 while (_Clock::now() < __t)
461 __cv.wait_until(__lk, __t);
464 template <class _Duration>
465 inline _LIBCPP_INLINE_VISIBILITY
467 sleep_until(const chrono::time_point<chrono::steady_clock, _Duration>& __t)
469 using namespace chrono;
470 sleep_for(__t - steady_clock::now());
473 inline _LIBCPP_INLINE_VISIBILITY
474 void yield() _NOEXCEPT {__libcpp_thread_yield();}
478 _LIBCPP_END_NAMESPACE_STD
480 #endif // !_LIBCPP_HAS_NO_THREADS
484 #endif // _LIBCPP_THREAD