libstdc++-v3/include/std/thread

   1 // <thread> -*- C++ -*-
   2
   3 // Copyright (C) 2008, 2009 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 2, 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 // You should have received a copy of the GNU General Public License
  17 // along with this library; see the file COPYING.  If not, write to
  18 // the Free Software Foundation, 51 Franklin Street, Fifth Floor,
  19 // Boston, MA 02110-1301, USA.
  20
  21 // As a special exception, you may use this file as part of a free software
  22 // library without restriction.  Specifically, if other files instantiate
  23 // templates or use macros or inline functions from this file, or you compile
  24 // this file and link it with other files to produce an executable, this
  25 // file does not by itself cause the resulting executable to be covered by
  26 // the GNU General Public License.  This exception does not however
  27 // invalidate any other reasons why the executable file might be covered by
  28 // the GNU General Public License.
  29
  30 /** @file thread
  31  *  This is a Standard C++ Library header.
  32  */
  33
  34 #ifndef _GLIBCXX_THREAD
  35 #define _GLIBCXX_THREAD 1
  36
  37 #pragma GCC system_header
  38
  39 #ifndef __GXX_EXPERIMENTAL_CXX0X__
  40 # include <c++0x_warning.h>
  41 #else
  42
  43 #include <chrono>
  44 #include <exception>
  45 #include <functional>
  46 #include <memory>
  47 #include <mutex>
  48 #include <condition_variable>
  49 #include <type_traits>
  50 #include <cstddef>
  51 #include <bits/functexcept.h>
  52 #include <bits/gthr.h>
  53
  54 #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
  55
  56 namespace std
  57 {
  58   class __thread_data_base;
  59
  60   typedef shared_ptr<__thread_data_base> __thread_data_ptr;
  61
  62   class __thread_data_base : public enable_shared_from_this<__thread_data_base>
  63   {
  64   public:
  65     __thread_data_base() = default;
  66     virtual ~__thread_data_base() = default;
  67
  68     virtual void _M_run() = 0;
  69
  70     __gthread_t         _M_thread_handle;
  71     __thread_data_ptr   _M_this_ptr;
  72     mutex               _M_data_mutex;
  73   };
  74
  75   template<typename _Callable>
  76     class __thread_data : public __thread_data_base
  77     {
  78     public:
  79       __thread_data(_Callable&& __f)
  80       : _M_func(std::forward<_Callable>(__f))
  81       { }
  82
  83       void _M_run()
  84       { _M_func(); }
  85
  86     private:
  87       _Callable _M_func;
  88     };
  89
  90   /// thread
  91   class thread
  92   {
  93   public:
  94     // types
  95     class id;
  96     typedef __gthread_t native_handle_type;
  97
  98     // cons
  99     thread() = default;
 100
 101     template<typename _Callable>
 102       explicit thread(_Callable __f)
 103       : _M_thread_data(_M_make_thread_data(__f))
 104       { _M_start_thread(); }
 105
 106     template<typename _Callable, typename... _Args>
 107       thread(_Callable&& __f, _Args&&... __args)
 108       : _M_thread_data(_M_make_thread_data(std::bind(__f, __args...)))
 109       { _M_start_thread(); }
 110
 111     ~thread()
 112     { detach(); }
 113
 114     thread(const thread&) = delete;
 115     thread(thread&& __t)
 116     { swap(__t); }
 117
 118     thread& operator=(const thread&) = delete;
 119     thread& operator=(thread&& __t)
 120     {
 121       if (joinable())
 122         detach();
 123       swap(__t);
 124       return *this;
 125     }
 126
 127     // members
 128     void
 129     swap(thread&& __t)
 130     { std::swap(_M_thread_data, __t._M_thread_data); }
 131
 132     bool
 133     joinable() const;
 134
 135     void
 136     join();
 137
 138     void
 139     detach();
 140
 141     thread::id
 142     get_id() const;
 143
 144     native_handle_type
 145     native_handle()
 146     { return _M_thread_data->_M_thread_handle; }
 147
 148     // static members
 149     static unsigned hardware_concurrency();
 150
 151     __thread_data_ptr
 152     _M_get_thread_data() const
 153     {
 154       lock_guard<mutex> __l(_M_thread_data_mutex);
 155       return _M_thread_data;
 156     }
 157
 158   private:
 159     template<typename _Callable>
 160       __thread_data_ptr
 161       _M_make_thread_data(_Callable&& __f)
 162       {
 163         return __thread_data_ptr(
 164           new __thread_data<_Callable>(std::forward<_Callable>(__f)));
 165       }
 166
 167     __thread_data_ptr
 168     _M_make_thread_data(void(*__f)())
 169     { return __thread_data_ptr(new __thread_data<void(*)()>(__f)); }
 170
 171     void _M_start_thread();
 172
 173     __thread_data_ptr   _M_thread_data;
 174     mutable mutex       _M_thread_data_mutex;
 175   };
 176
 177   inline void
 178   swap(thread& __x, thread& __y)
 179   { __x.swap(__y); }
 180
 181   inline void
 182   swap(thread&& __x, thread& __y)
 183   { __x.swap(__y); }
 184
 185   inline void
 186   swap(thread& __x, thread&& __y)
 187   { __x.swap(__y); }
 188
 189   namespace this_thread
 190   {
 191     thread::id
 192     get_id();
 193
 194 #ifdef _GLIBCXX_USE_SCHED_YIELD
 195     inline void
 196     yield()
 197     { __gthread_yield(); }
 198 #endif
 199
 200 #ifdef _GLIBCXX_USE_NANOSLEEP
 201     template<typename _Clock, typename _Duration>
 202       inline void
 203       sleep_until(const chrono::time_point<_Clock, _Duration>& __atime)
 204       { sleep_for(__atime - _Clock::now()); }
 205
 206     template<typename _Rep, typename _Period>
 207       inline void
 208       sleep_for(const chrono::duration<_Rep, _Period>& __rtime)
 209       {
 210         chrono::seconds __s =
 211           chrono::duration_cast<chrono::seconds>(__rtime);
 212
 213         chrono::nanoseconds __ns =
 214           chrono::duration_cast<chrono::nanoseconds>(__rtime - __s);
 215
 216         __gthread_time_t __ts =
 217           {
 218             static_cast<std::time_t>(__s.count()),
 219             static_cast<long>(__ns.count())
 220           };
 221
 222         ::nanosleep(&__ts, 0);
 223       }
 224 #endif
 225   }
 226
 227   /// thread::id
 228   class thread::id
 229   {
 230   public:
 231     id() : _M_thread_id() { }
 232
 233   private:
 234     friend class thread;
 235
 236     friend thread::id this_thread::get_id();
 237
 238     friend bool
 239     operator==(thread::id __x, thread::id __y)
 240     { return static_cast<bool>(__gthread_equal(__x._M_thread_id,
 241                                                __y._M_thread_id)); }
 242
 243     friend bool
 244     operator<(thread::id __x, thread::id __y)
 245     { return __x._M_thread_id < __y._M_thread_id; }
 246
 247     template<class _CharT, class _Traits>
 248       friend basic_ostream<_CharT, _Traits>&
 249       operator<<(basic_ostream<_CharT, _Traits>&& __out, thread::id __id);
 250
 251     id(__gthread_t __id)
 252     : _M_thread_id(__id)
 253     { }
 254
 255     __gthread_t _M_thread_id;
 256   };
 257
 258   inline bool
 259   operator!=(thread::id __x, thread::id __y)
 260   { return !(__x == __y); }
 261
 262   inline bool
 263   operator<=(thread::id __x, thread::id __y)
 264   { return !(__y < __x); }
 265
 266   inline bool
 267   operator>(thread::id __x, thread::id __y)
 268   { return __y < __x; }
 269
 270   inline bool
 271   operator>=(thread::id __x, thread::id __y)
 272   { return !(__x < __y); }
 273
 274   template<class _CharT, class _Traits>
 275     inline basic_ostream<_CharT, _Traits>&
 276     operator<<(basic_ostream<_CharT, _Traits>&& __out, thread::id __id)
 277     {
 278       if(__id == thread::id())
 279         return __out << "non-executing thread";
 280       else
 281         return __out << __id._M_thread_id;
 282     }
 283
 284   inline bool
 285   thread::joinable() const
 286   { return get_id() != thread::id(); }
 287
 288   inline thread::id
 289   thread::get_id() const
 290   {
 291     if(_M_thread_data)
 292       return thread::id(_M_thread_data->_M_thread_handle);
 293     else
 294       return thread::id();
 295   }
 296
 297   namespace this_thread
 298   {
 299     inline thread::id
 300     get_id()
 301     { return thread::id(__gthread_self()); }
 302   }
 303 }
 304
 305 #endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1
 306
 307 #endif // __GXX_EXPERIMENTAL_CXX0X__
 308
 309 #endif // _GLIBCXX_THREAD