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_HAS_NO_VARIADICS
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 __at_thread_exit(void*);
153 typedef _Tp* pointer;
155 ~__thread_specific_ptr();
157 _LIBCPP_INLINE_VISIBILITY
158 pointer get() const {return static_cast<_Tp*>(__libcpp_tls_get(__key_));}
159 _LIBCPP_INLINE_VISIBILITY
160 pointer operator*() const {return *get();}
161 _LIBCPP_INLINE_VISIBILITY
162 pointer operator->() const {return get();}
163 void set_pointer(pointer __p);
168 __thread_specific_ptr<_Tp>::__at_thread_exit(void* __p)
170 delete static_cast<pointer>(__p);
174 __thread_specific_ptr<_Tp>::__thread_specific_ptr()
176 int __ec = __libcpp_tls_create(
178 &__thread_specific_ptr::__at_thread_exit);
180 __throw_system_error(__ec,
181 "__thread_specific_ptr construction failed");
185 __thread_specific_ptr<_Tp>::~__thread_specific_ptr()
187 // __thread_specific_ptr is only created with a static storage duration
188 // so this destructor is only invoked during program termination. Invoking
189 // pthread_key_delete(__key_) may prevent other threads from deleting their
190 // thread local data. For this reason we leak the key.
195 __thread_specific_ptr<_Tp>::set_pointer(pointer __p)
197 _LIBCPP_ASSERT(get() == nullptr,
198 "Attempting to overwrite thread local data");
199 __libcpp_tls_set(__key_, __p);
202 class _LIBCPP_TYPE_VIS thread;
203 class _LIBCPP_TYPE_VIS __thread_id;
205 namespace this_thread
208 _LIBCPP_INLINE_VISIBILITY __thread_id get_id() _NOEXCEPT;
212 template<> struct hash<__thread_id>;
214 class _LIBCPP_TYPE_VIS_ONLY __thread_id
216 // FIXME: pthread_t is a pointer on Darwin but a long on Linux.
217 // NULL is the no-thread value on Darwin. Someone needs to check
218 // on other platforms. We assume 0 works everywhere for now.
219 __libcpp_thread_id __id_;
222 _LIBCPP_INLINE_VISIBILITY
223 __thread_id() _NOEXCEPT : __id_(0) {}
225 friend _LIBCPP_INLINE_VISIBILITY
226 bool operator==(__thread_id __x, __thread_id __y) _NOEXCEPT
227 {return __libcpp_thread_id_equal(__x.__id_, __y.__id_);}
228 friend _LIBCPP_INLINE_VISIBILITY
229 bool operator!=(__thread_id __x, __thread_id __y) _NOEXCEPT
230 {return !(__x == __y);}
231 friend _LIBCPP_INLINE_VISIBILITY
232 bool operator< (__thread_id __x, __thread_id __y) _NOEXCEPT
233 {return __libcpp_thread_id_less(__x.__id_, __y.__id_);}
234 friend _LIBCPP_INLINE_VISIBILITY
235 bool operator<=(__thread_id __x, __thread_id __y) _NOEXCEPT
236 {return !(__y < __x);}
237 friend _LIBCPP_INLINE_VISIBILITY
238 bool operator> (__thread_id __x, __thread_id __y) _NOEXCEPT
240 friend _LIBCPP_INLINE_VISIBILITY
241 bool operator>=(__thread_id __x, __thread_id __y) _NOEXCEPT
242 {return !(__x < __y);}
244 template<class _CharT, class _Traits>
246 _LIBCPP_INLINE_VISIBILITY
247 basic_ostream<_CharT, _Traits>&
248 operator<<(basic_ostream<_CharT, _Traits>& __os, __thread_id __id)
249 {return __os << __id.__id_;}
252 _LIBCPP_INLINE_VISIBILITY
253 __thread_id(__libcpp_thread_id __id) : __id_(__id) {}
255 friend __thread_id this_thread::get_id() _NOEXCEPT;
256 friend class _LIBCPP_TYPE_VIS thread;
257 friend struct _LIBCPP_TYPE_VIS_ONLY hash<__thread_id>;
261 struct _LIBCPP_TYPE_VIS_ONLY hash<__thread_id>
262 : public unary_function<__thread_id, size_t>
264 _LIBCPP_INLINE_VISIBILITY
265 size_t operator()(__thread_id __v) const
267 return hash<__libcpp_thread_id>()(__v.__id_);
271 namespace this_thread
274 inline _LIBCPP_INLINE_VISIBILITY
278 return __libcpp_thread_get_current_id();
283 class _LIBCPP_TYPE_VIS thread
285 __libcpp_thread_t __t_;
287 thread(const thread&);
288 thread& operator=(const thread&);
290 typedef __thread_id id;
291 typedef __libcpp_thread_t native_handle_type;
293 _LIBCPP_INLINE_VISIBILITY
294 thread() _NOEXCEPT : __t_(0) {}
295 #ifndef _LIBCPP_HAS_NO_VARIADICS
296 template <class _Fp, class ..._Args,
297 class = typename enable_if
299 !is_same<typename decay<_Fp>::type, thread>::value
302 explicit thread(_Fp&& __f, _Args&&... __args);
303 #else // _LIBCPP_HAS_NO_VARIADICS
304 template <class _Fp> explicit thread(_Fp __f);
308 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
309 _LIBCPP_INLINE_VISIBILITY
310 thread(thread&& __t) _NOEXCEPT : __t_(__t.__t_) {__t.__t_ = 0;}
311 _LIBCPP_INLINE_VISIBILITY
312 thread& operator=(thread&& __t) _NOEXCEPT;
313 #endif // _LIBCPP_HAS_NO_RVALUE_REFERENCES
315 _LIBCPP_INLINE_VISIBILITY
316 void swap(thread& __t) _NOEXCEPT {_VSTD::swap(__t_, __t.__t_);}
318 _LIBCPP_INLINE_VISIBILITY
319 bool joinable() const _NOEXCEPT {return __t_ != 0;}
322 _LIBCPP_INLINE_VISIBILITY
323 id get_id() const _NOEXCEPT {return __libcpp_thread_get_id(&__t_);}
324 _LIBCPP_INLINE_VISIBILITY
325 native_handle_type native_handle() _NOEXCEPT {return __t_;}
327 static unsigned hardware_concurrency() _NOEXCEPT;
330 #ifndef _LIBCPP_HAS_NO_VARIADICS
332 template <class _TSp, class _Fp, class ..._Args, size_t ..._Indices>
333 inline _LIBCPP_INLINE_VISIBILITY
335 __thread_execute(tuple<_TSp, _Fp, _Args...>& __t, __tuple_indices<_Indices...>)
337 __invoke(_VSTD::move(_VSTD::get<1>(__t)), _VSTD::move(_VSTD::get<_Indices>(__t))...);
341 void* __thread_proxy(void* __vp)
343 // _Fp = std::tuple< unique_ptr<__thread_struct>, Functor, Args...>
344 std::unique_ptr<_Fp> __p(static_cast<_Fp*>(__vp));
345 __thread_local_data().set_pointer(_VSTD::get<0>(*__p).release());
346 typedef typename __make_tuple_indices<tuple_size<_Fp>::value, 2>::type _Index;
347 __thread_execute(*__p, _Index());
351 template <class _Fp, class ..._Args,
354 thread::thread(_Fp&& __f, _Args&&... __args)
356 typedef unique_ptr<__thread_struct> _TSPtr;
357 _TSPtr __tsp(new __thread_struct);
358 typedef tuple<_TSPtr, typename decay<_Fp>::type, typename decay<_Args>::type...> _Gp;
359 _VSTD::unique_ptr<_Gp> __p(
360 new _Gp(std::move(__tsp),
361 __decay_copy(_VSTD::forward<_Fp>(__f)),
362 __decay_copy(_VSTD::forward<_Args>(__args))...));
363 int __ec = __libcpp_thread_create(&__t_, &__thread_proxy<_Gp>, __p.get());
367 __throw_system_error(__ec, "thread constructor failed");
370 #else // _LIBCPP_HAS_NO_VARIADICS
373 struct __thread_invoke_pair {
374 // This type is used to pass memory for thread local storage and a functor
375 // to a newly created thread because std::pair doesn't work with
376 // std::unique_ptr in C++03.
377 __thread_invoke_pair(_Fp& __f) : __tsp_(new __thread_struct), __fn_(__f) {}
378 unique_ptr<__thread_struct> __tsp_;
383 void* __thread_proxy_cxx03(void* __vp)
385 std::unique_ptr<_Fp> __p(static_cast<_Fp*>(__vp));
386 __thread_local_data().set_pointer(__p->__tsp_.release());
392 thread::thread(_Fp __f)
395 typedef __thread_invoke_pair<_Fp> _InvokePair;
396 typedef std::unique_ptr<_InvokePair> _PairPtr;
397 _PairPtr __pp(new _InvokePair(__f));
398 int __ec = __libcpp_thread_create(&__t_, &__thread_proxy_cxx03<_InvokePair>, __pp.get());
402 __throw_system_error(__ec, "thread constructor failed");
405 #endif // _LIBCPP_HAS_NO_VARIADICS
407 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
411 thread::operator=(thread&& __t) _NOEXCEPT
420 #endif // _LIBCPP_HAS_NO_RVALUE_REFERENCES
422 inline _LIBCPP_INLINE_VISIBILITY
423 void swap(thread& __x, thread& __y) _NOEXCEPT {__x.swap(__y);}
425 namespace this_thread
428 _LIBCPP_FUNC_VIS void sleep_for(const chrono::nanoseconds& ns);
430 template <class _Rep, class _Period>
432 sleep_for(const chrono::duration<_Rep, _Period>& __d)
434 using namespace chrono;
435 if (__d > duration<_Rep, _Period>::zero())
437 _LIBCPP_CONSTEXPR duration<long double> _Max = nanoseconds::max();
441 __ns = duration_cast<nanoseconds>(__d);
446 __ns = nanoseconds::max();
451 template <class _Clock, class _Duration>
453 sleep_until(const chrono::time_point<_Clock, _Duration>& __t)
455 using namespace chrono;
457 condition_variable __cv;
458 unique_lock<mutex> __lk(__mut);
459 while (_Clock::now() < __t)
460 __cv.wait_until(__lk, __t);
463 template <class _Duration>
464 inline _LIBCPP_INLINE_VISIBILITY
466 sleep_until(const chrono::time_point<chrono::steady_clock, _Duration>& __t)
468 using namespace chrono;
469 sleep_for(__t - steady_clock::now());
472 inline _LIBCPP_INLINE_VISIBILITY
473 void yield() _NOEXCEPT {__libcpp_thread_yield();}
477 _LIBCPP_END_NAMESPACE_STD
479 #endif // !_LIBCPP_HAS_NO_THREADS
481 #endif // _LIBCPP_THREAD