1 // -*- C++ -*- 2 //===----------------------------------------------------------------------===// 3 // 4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5 // See https://llvm.org/LICENSE.txt for license information. 6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7 // 8 //===----------------------------------------------------------------------===// 9 10 #ifndef _LIBCPP___THREAD_ID_H 11 #define _LIBCPP___THREAD_ID_H 12 13 #include <__compare/ordering.h> 14 #include <__config> 15 #include <__fwd/hash.h> 16 #include <__threading_support> 17 #include <iosfwd> 18 19 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 20 # pragma GCC system_header 21 #endif 22 23 _LIBCPP_BEGIN_NAMESPACE_STD 24 25 #ifndef _LIBCPP_HAS_NO_THREADS 26 class _LIBCPP_EXPORTED_FROM_ABI __thread_id; 27 28 namespace this_thread { 29 30 _LIBCPP_HIDE_FROM_ABI __thread_id get_id() _NOEXCEPT; 31 32 } // namespace this_thread 33 34 template <> 35 struct hash<__thread_id>; 36 37 class _LIBCPP_TEMPLATE_VIS __thread_id { 38 // FIXME: pthread_t is a pointer on Darwin but a long on Linux. 39 // NULL is the no-thread value on Darwin. Someone needs to check 40 // on other platforms. We assume 0 works everywhere for now. 41 __libcpp_thread_id __id_; 42 43 static _LIBCPP_HIDE_FROM_ABI bool 44 __lt_impl(__thread_id __x, __thread_id __y) _NOEXCEPT { // id==0 is always less than any other thread_id 45 if (__x.__id_ == 0) 46 return __y.__id_ != 0; 47 if (__y.__id_ == 0) 48 return false; 49 return __libcpp_thread_id_less(__x.__id_, __y.__id_); 50 } 51 52 public: 53 _LIBCPP_HIDE_FROM_ABI __thread_id() _NOEXCEPT : __id_(0) {} 54 55 _LIBCPP_HIDE_FROM_ABI void __reset() { __id_ = 0; } 56 57 friend _LIBCPP_HIDE_FROM_ABI bool operator==(__thread_id __x, __thread_id __y) _NOEXCEPT; 58 # if _LIBCPP_STD_VER <= 17 59 friend _LIBCPP_HIDE_FROM_ABI bool operator<(__thread_id __x, __thread_id __y) _NOEXCEPT; 60 # else // _LIBCPP_STD_VER <= 17 61 friend _LIBCPP_HIDE_FROM_ABI strong_ordering operator<=>(__thread_id __x, __thread_id __y) noexcept; 62 # endif // _LIBCPP_STD_VER <= 17 63 64 template <class _CharT, class _Traits> 65 friend _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>& 66 operator<<(basic_ostream<_CharT, _Traits>& __os, __thread_id __id); 67 68 private: 69 _LIBCPP_HIDE_FROM_ABI __thread_id(__libcpp_thread_id __id) : __id_(__id) {} 70 71 _LIBCPP_HIDE_FROM_ABI friend __libcpp_thread_id __get_underlying_id(const __thread_id __id) { return __id.__id_; } 72 73 friend __thread_id this_thread::get_id() _NOEXCEPT; 74 friend class _LIBCPP_EXPORTED_FROM_ABI thread; 75 friend struct _LIBCPP_TEMPLATE_VIS hash<__thread_id>; 76 }; 77 78 inline _LIBCPP_HIDE_FROM_ABI bool operator==(__thread_id __x, __thread_id __y) _NOEXCEPT { 79 // Don't pass id==0 to underlying routines 80 if (__x.__id_ == 0) 81 return __y.__id_ == 0; 82 if (__y.__id_ == 0) 83 return false; 84 return __libcpp_thread_id_equal(__x.__id_, __y.__id_); 85 } 86 87 # if _LIBCPP_STD_VER <= 17 88 89 inline _LIBCPP_HIDE_FROM_ABI bool operator!=(__thread_id __x, __thread_id __y) _NOEXCEPT { return !(__x == __y); } 90 91 inline _LIBCPP_HIDE_FROM_ABI bool operator<(__thread_id __x, __thread_id __y) _NOEXCEPT { 92 return __thread_id::__lt_impl(__x.__id_, __y.__id_); 93 } 94 95 inline _LIBCPP_HIDE_FROM_ABI bool operator<=(__thread_id __x, __thread_id __y) _NOEXCEPT { return !(__y < __x); } 96 inline _LIBCPP_HIDE_FROM_ABI bool operator>(__thread_id __x, __thread_id __y) _NOEXCEPT { return __y < __x; } 97 inline _LIBCPP_HIDE_FROM_ABI bool operator>=(__thread_id __x, __thread_id __y) _NOEXCEPT { return !(__x < __y); } 98 99 # else // _LIBCPP_STD_VER <= 17 100 101 inline _LIBCPP_HIDE_FROM_ABI strong_ordering operator<=>(__thread_id __x, __thread_id __y) noexcept { 102 if (__x == __y) 103 return strong_ordering::equal; 104 if (__thread_id::__lt_impl(__x, __y)) 105 return strong_ordering::less; 106 return strong_ordering::greater; 107 } 108 109 # endif // _LIBCPP_STD_VER <= 17 110 111 namespace this_thread { 112 113 inline _LIBCPP_HIDE_FROM_ABI __thread_id get_id() _NOEXCEPT { return __libcpp_thread_get_current_id(); } 114 115 } // namespace this_thread 116 117 #endif // !_LIBCPP_HAS_NO_THREADS 118 119 _LIBCPP_END_NAMESPACE_STD 120 121 #endif // _LIBCPP___THREAD_ID_H 122