# thread

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    00001 // <thread> -*- C++ -*-
    00002
    00003 // Copyright (C) 2008, 2009 Free Software Foundation, Inc.
    00004 //
    00005 // This file is part of the GNU ISO C++ Library.  This library is free
    00006 // software; you can redistribute it and/or modify it under the
    00007 // terms of the GNU General Public License as published by the
    00008 // Free Software Foundation; either version 3, or (at your option)
    00009 // any later version.
    00010
    00011 // This library is distributed in the hope that it will be useful,
    00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of
    00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    00014 // GNU General Public License for more details.
    00015
    00016 // Under Section 7 of GPL version 3, you are granted additional
    00017 // permissions described in the GCC Runtime Library Exception, version
    00018 // 3.1, as published by the Free Software Foundation.
    00019
    00020 // You should have received a copy of the GNU General Public License and
    00021 // a copy of the GCC Runtime Library Exception along with this program;
    00022 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
    00023 // <http://www.gnu.org/licenses/>.
    00024
    00025 /** @file thread
    00026  *  This is a Standard C++ Library header.
    00027  */
    00028
    00029 #ifndef _GLIBCXX_THREAD
    00030 #define _GLIBCXX_THREAD 1
    00031
    00032 #pragma GCC system_header
    00033
    00034 #ifndef __GXX_EXPERIMENTAL_CXX0X__
    00035 # include <c++0x_warning.h>
    00036 #else
    00037
    00038 #include <chrono>
    00039 #include <functional>
    00040 #include <memory>
    00041 #include <mutex>
    00042 #include <condition_variable>
    00043 #include <cstddef>
    00044 #include <bits/functexcept.h>
    00045 #include <bits/gthr.h>
    00046
    00047 #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
    00048
    00049 namespace std
    00050 {
    00051   /**
    00052    * @defgroup threads Threads
    00053    * @ingroup concurrency
    00054    *
    00055    * Classes for thread support.
    00056    * @{
    00057    */
    00058
    00059   /// thread
    00060   class thread
    00061   {
    00062   public:
    00063     typedef __gthread_t         native_handle_type;
    00064     struct _Impl_base;
    00065     typedef shared_ptr<_Impl_base>  __shared_base_type;
    00066
    00067     /// thread::id
    00068     class id
    00069     {
    00070       native_handle_type    _M_thread;
    00071
    00072     public:
    00073       id() : _M_thread() { }
    00074
    00075       explicit
    00076       id(native_handle_type __id) : _M_thread(__id) { }
    00077
    00078     private:
    00079       friend class thread;
    00080
    00081       friend bool
    00082       operator==(thread::id __x, thread::id __y)
    00083       { return __gthread_equal(__x._M_thread, __y._M_thread); }
    00084
    00085       friend bool
    00086       operator<(thread::id __x, thread::id __y)
    00087       { return __x._M_thread < __y._M_thread; }
    00088
    00089       template<class _CharT, class _Traits>
    00090     friend basic_ostream<_CharT, _Traits>&
    00091     operator<<(basic_ostream<_CharT, _Traits>&& __out, thread::id __id);
    00092     };
    00093
    00094     // Simple base type that the templatized, derived class containing
    00095     // an arbitrary functor can be converted to and called.
    00096     struct _Impl_base
    00097     {
    00098       __shared_base_type    _M_this_ptr;
    00099
    00100       virtual ~_Impl_base() = default;
    00101
    00102       virtual void _M_run() = 0;
    00103     };
    00104
    00105     template<typename _Callable>
    00106       struct _Impl : public _Impl_base
    00107       {
    00108     _Callable       _M_func;
    00109
    00110     _Impl(_Callable&& __f) : _M_func(std::forward<_Callable>(__f))
    00111     { }
    00112
    00113     void
    00114     _M_run() { _M_func(); }
    00115       };
    00116
    00117   private:
    00118     id              _M_id;
    00119
    00120   public:
    00121     thread() = default;
    00122     thread(const thread&) = delete;
    00123
    00124     thread(thread&& __t)
    00125     { swap(__t); }
    00126
    00127     template<typename _Callable>
    00128       explicit thread(_Callable __f)
    00129       { _M_start_thread(_M_make_routine<_Callable>(__f)); }
    00130
    00131     template<typename _Callable, typename... _Args>
    00132       thread(_Callable&& __f, _Args&&... __args)
    00133       { _M_start_thread(_M_make_routine(std::bind(__f, __args...))); }
    00134
    00135     ~thread()
    00136     {
    00137       if (joinable())
    00138     detach();
    00139     }
    00140
    00141     thread& operator=(const thread&) = delete;
    00142
    00143     thread& operator=(thread&& __t)
    00144     {
    00145       if (joinable())
    00146     detach();
    00147       swap(__t);
    00148       return *this;
    00149     }
    00150
    00151     void
    00152     swap(thread&& __t)
    00153     { std::swap(_M_id, __t._M_id); }
    00154
    00155     bool
    00156     joinable() const
    00157     { return !(_M_id == id()); }
    00158
    00159     void
    00160     join();
    00161
    00162     void
    00163     detach();
    00164
    00165     thread::id
    00166     get_id() const
    00167     { return _M_id; }
    00168
    00169     /** @pre thread is joinable
    00170      */
    00171     native_handle_type
    00172     native_handle()
    00173     { return _M_id._M_thread; }
    00174
    00175     // Returns a value that hints at the number of hardware thread contexts.
    00176     static unsigned int
    00177     hardware_concurrency()
    00178     { return 0; }
    00179
    00180   private:
    00181     void
    00182     _M_start_thread(__shared_base_type);
    00183
    00184     template<typename _Callable>
    00185       shared_ptr<_Impl<_Callable>>
    00186       _M_make_routine(_Callable&& __f)
    00187       {
    00188     // Create and allocate full data structure, not base.
    00189     return make_shared<_Impl<_Callable>>(std::forward<_Callable>(__f));
    00190       }
    00191   };
    00192
    00193   inline void
    00194   swap(thread& __x, thread& __y)
    00195   { __x.swap(__y); }
    00196
    00197   inline void
    00198   swap(thread&& __x, thread& __y)
    00199   { __x.swap(__y); }
    00200
    00201   inline void
    00202   swap(thread& __x, thread&& __y)
    00203   { __x.swap(__y); }
    00204
    00205   inline bool
    00206   operator!=(thread::id __x, thread::id __y)
    00207   { return !(__x == __y); }
    00208
    00209   inline bool
    00210   operator<=(thread::id __x, thread::id __y)
    00211   { return !(__y < __x); }
    00212
    00213   inline bool
    00214   operator>(thread::id __x, thread::id __y)
    00215   { return __y < __x; }
    00216
    00217   inline bool
    00218   operator>=(thread::id __x, thread::id __y)
    00219   { return !(__x < __y); }
    00220
    00221   template<class _CharT, class _Traits>
    00222     inline basic_ostream<_CharT, _Traits>&
    00223     operator<<(basic_ostream<_CharT, _Traits>&& __out, thread::id __id)
    00224     {
    00225       if (__id == thread::id())
    00226     return __out << "thread::id of a non-executing thread";
    00227       else
    00228     return __out << __id._M_thread;
    00229     }
    00230
    00231   /** @namespace std::this_thread
    00232    *  @brief ISO C++ 0x entities sub namespace for thread.
    00233    *  30.2.2 Namespace this_thread.
    00234    */
    00235   namespace this_thread
    00236   {
    00237     /// get_id
    00238     inline thread::id
    00239     get_id() { return thread::id(__gthread_self()); }
    00240
    00241 #ifdef _GLIBCXX_USE_SCHED_YIELD
    00242     /// yield
    00243     inline void
    00244     yield()
    00245     { __gthread_yield(); }
    00246 #endif
    00247
    00248 #ifdef _GLIBCXX_USE_NANOSLEEP
    00249     /// sleep_until
    00250     template<typename _Clock, typename _Duration>
    00251       inline void
    00252       sleep_until(const chrono::time_point<_Clock, _Duration>& __atime)
    00253       { sleep_for(__atime - _Clock::now()); }
    00254
    00255     /// sleep_for
    00256     template<typename _Rep, typename _Period>
    00257       inline void
    00258       sleep_for(const chrono::duration<_Rep, _Period>& __rtime)
    00259       {
    00260     chrono::seconds __s =
    00261       chrono::duration_cast<chrono::seconds>(__rtime);
    00262
    00263     chrono::nanoseconds __ns =
    00264       chrono::duration_cast<chrono::nanoseconds>(__rtime - __s);
    00265
    00266     __gthread_time_t __ts =
    00267       {
    00268         static_cast<std::time_t>(__s.count()),
    00269         static_cast<long>(__ns.count())
    00270       };
    00271
    00272     ::nanosleep(&__ts, 0);
    00273       }
    00274 #endif
    00275   }
    00276
    00277   // @} group threads
    00278 }
    00279
    00280 #endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1
    00281
    00282 #endif // __GXX_EXPERIMENTAL_CXX0X__
    00283
    00284 #endif // _GLIBCXX_THREAD