libstdc++
thread
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00001 // <thread> -*- C++ -*-
00002 
00003 // Copyright (C) 2008, 2009, 2010, 2011 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 include/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 <bits/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 <bits/functexcept.h>
00044 #include <bits/functional_hash.h>
00045 #include <bits/gthr.h>
00046 
00047 #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
00048 
00049 namespace std _GLIBCXX_VISIBILITY(default)
00050 {
00051 _GLIBCXX_BEGIN_NAMESPACE_VERSION
00052 
00053   /**
00054    * @defgroup threads Threads
00055    * @ingroup concurrency
00056    *
00057    * Classes for thread support.
00058    * @{
00059    */
00060 
00061   /// thread
00062   class thread
00063   {
00064   public:
00065     typedef __gthread_t         native_handle_type;
00066     struct _Impl_base;
00067     typedef shared_ptr<_Impl_base>  __shared_base_type;
00068 
00069     /// thread::id
00070     class id
00071     {
00072       native_handle_type    _M_thread;
00073 
00074     public:
00075       id() : _M_thread() { }
00076 
00077       explicit
00078       id(native_handle_type __id) : _M_thread(__id) { }
00079 
00080     private:
00081       friend class thread;
00082       friend class hash<thread::id>;
00083 
00084       friend bool
00085       operator==(thread::id __x, thread::id __y)
00086       { return __gthread_equal(__x._M_thread, __y._M_thread); }
00087 
00088       friend bool
00089       operator<(thread::id __x, thread::id __y)
00090       { return __x._M_thread < __y._M_thread; }
00091 
00092       template<class _CharT, class _Traits>
00093     friend basic_ostream<_CharT, _Traits>&
00094     operator<<(basic_ostream<_CharT, _Traits>& __out, thread::id __id);
00095     };
00096 
00097     // Simple base type that the templatized, derived class containing
00098     // an arbitrary functor can be converted to and called.
00099     struct _Impl_base
00100     {
00101       __shared_base_type    _M_this_ptr;
00102 
00103       inline virtual ~_Impl_base();
00104 
00105       virtual void _M_run() = 0;
00106     };
00107 
00108     template<typename _Callable>
00109       struct _Impl : public _Impl_base
00110       {
00111     _Callable       _M_func;
00112 
00113     _Impl(_Callable&& __f) : _M_func(std::forward<_Callable>(__f))
00114     { }
00115 
00116     void
00117     _M_run() { _M_func(); }
00118       };
00119 
00120   private:
00121     id              _M_id;
00122 
00123   public:
00124     thread() = default;
00125     thread(thread&) = delete;
00126     thread(const thread&) = delete;
00127 
00128     thread(thread&& __t)
00129     { swap(__t); }
00130 
00131     template<typename _Callable, typename... _Args>
00132       explicit 
00133       thread(_Callable&& __f, _Args&&... __args)
00134       {
00135         _M_start_thread(_M_make_routine(std::bind<void>(
00136                 std::forward<_Callable>(__f),
00137                 std::forward<_Args>(__args)...)));
00138       }
00139 
00140     ~thread()
00141     {
00142       if (joinable())
00143     std::terminate();
00144     }
00145 
00146     thread& operator=(const thread&) = delete;
00147 
00148     thread& operator=(thread&& __t)
00149     {
00150       if (joinable())
00151     std::terminate();
00152       swap(__t);
00153       return *this;
00154     }
00155 
00156     void
00157     swap(thread& __t)
00158     { std::swap(_M_id, __t._M_id); }
00159 
00160     bool
00161     joinable() const
00162     { return !(_M_id == id()); }
00163 
00164     void
00165     join();
00166 
00167     void
00168     detach();
00169 
00170     thread::id
00171     get_id() const
00172     { return _M_id; }
00173 
00174     /** @pre thread is joinable
00175      */
00176     native_handle_type
00177     native_handle()
00178     { return _M_id._M_thread; }
00179 
00180     // Returns a value that hints at the number of hardware thread contexts.
00181     static unsigned int
00182     hardware_concurrency()
00183     { return 0; }
00184 
00185   private:
00186     void
00187     _M_start_thread(__shared_base_type);
00188 
00189     template<typename _Callable>
00190       shared_ptr<_Impl<_Callable>>
00191       _M_make_routine(_Callable&& __f)
00192       {
00193     // Create and allocate full data structure, not base.
00194     return make_shared<_Impl<_Callable>>(std::forward<_Callable>(__f));
00195       }
00196   };
00197 
00198   inline thread::_Impl_base::~_Impl_base() = default;
00199 
00200   inline void
00201   swap(thread& __x, thread& __y)
00202   { __x.swap(__y); }
00203 
00204   inline bool
00205   operator!=(thread::id __x, thread::id __y)
00206   { return !(__x == __y); }
00207 
00208   inline bool
00209   operator<=(thread::id __x, thread::id __y)
00210   { return !(__y < __x); }
00211 
00212   inline bool
00213   operator>(thread::id __x, thread::id __y)
00214   { return __y < __x; }
00215 
00216   inline bool
00217   operator>=(thread::id __x, thread::id __y)
00218   { return !(__x < __y); }
00219 
00220   // DR 889.
00221   /// std::hash specialization for thread::id.
00222   template<>
00223     struct hash<thread::id>
00224     : public __hash_base<size_t, thread::id>
00225     {
00226       size_t
00227       operator()(const thread::id& __id) const
00228       { return std::_Hash_impl::hash(__id._M_thread); }
00229     };
00230 
00231   template<class _CharT, class _Traits>
00232     inline basic_ostream<_CharT, _Traits>&
00233     operator<<(basic_ostream<_CharT, _Traits>& __out, thread::id __id)
00234     {
00235       if (__id == thread::id())
00236     return __out << "thread::id of a non-executing thread";
00237       else
00238     return __out << __id._M_thread;
00239     }
00240 
00241 _GLIBCXX_END_NAMESPACE_VERSION
00242 
00243   /** @namespace std::this_thread
00244    *  @brief ISO C++ 0x entities sub namespace for thread.
00245    *  30.2.2 Namespace this_thread.
00246    */
00247   namespace this_thread
00248   {
00249   _GLIBCXX_BEGIN_NAMESPACE_VERSION
00250 
00251     /// get_id
00252     inline thread::id
00253     get_id() { return thread::id(__gthread_self()); }
00254 
00255 #ifdef _GLIBCXX_USE_SCHED_YIELD
00256     /// yield
00257     inline void
00258     yield()
00259     { __gthread_yield(); }
00260 #endif
00261 
00262 #ifdef _GLIBCXX_USE_NANOSLEEP
00263     /// sleep_until
00264     template<typename _Clock, typename _Duration>
00265       inline void
00266       sleep_until(const chrono::time_point<_Clock, _Duration>& __atime)
00267       { sleep_for(__atime - _Clock::now()); }
00268 
00269     /// sleep_for
00270     template<typename _Rep, typename _Period>
00271       inline void
00272       sleep_for(const chrono::duration<_Rep, _Period>& __rtime)
00273       {
00274     chrono::seconds __s =
00275       chrono::duration_cast<chrono::seconds>(__rtime);
00276 
00277     chrono::nanoseconds __ns =
00278       chrono::duration_cast<chrono::nanoseconds>(__rtime - __s);
00279 
00280     __gthread_time_t __ts =
00281       {
00282         static_cast<std::time_t>(__s.count()),
00283         static_cast<long>(__ns.count())
00284       };
00285 
00286     ::nanosleep(&__ts, 0);
00287       }
00288 #endif
00289 
00290   _GLIBCXX_END_NAMESPACE_VERSION
00291   }
00292 
00293   // @} group threads
00294 
00295 } // namespace
00296 
00297 #endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1
00298 
00299 #endif // __GXX_EXPERIMENTAL_CXX0X__
00300 
00301 #endif // _GLIBCXX_THREAD