# thread

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