# condition_variable

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    00001 // <condition_variable> -*- 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 condition_variable
    00026  *  This is a Standard C++ Library header.
    00027  */
    00028
    00029 #ifndef _GLIBCXX_CONDITION_VARIABLE
    00030 #define _GLIBCXX_CONDITION_VARIABLE 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 <mutex> // unique_lock
    00040
    00041 #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
    00042
    00043 namespace std
    00044 {
    00045   /**
    00046    * @defgroup condition_variables Condition Variables
    00047    * @ingroup concurrency
    00048    *
    00049    * Classes for condition_variable support.
    00050    * @{
    00051    */
    00052
    00053   /// condition_variable
    00054   class condition_variable
    00055   {
    00056     typedef chrono::system_clock    __clock_t;
    00057     typedef __gthread_cond_t        __native_type;
    00058     __native_type           _M_cond;
    00059
    00060   public:
    00061     typedef __native_type*      native_handle_type;
    00062
    00063     condition_variable();
    00064     ~condition_variable();
    00065
    00066     condition_variable(const condition_variable&) = delete;
    00067     condition_variable& operator=(const condition_variable&) = delete;
    00068
    00069     void
    00070     notify_one();
    00071
    00072     void
    00073     notify_all();
    00074
    00075     void
    00076     wait(unique_lock<mutex>& __lock);
    00077
    00078     template<typename _Predicate>
    00079       void
    00080       wait(unique_lock<mutex>& __lock, _Predicate __p)
    00081       {
    00082     while (!__p())
    00083       wait(__lock);
    00084       }
    00085
    00086     template<typename _Duration>
    00087       bool
    00088       wait_until(unique_lock<mutex>& __lock,
    00089          const chrono::time_point<__clock_t, _Duration>& __atime)
    00090       { return __wait_until_impl(__lock, __atime); }
    00091
    00092     template<typename _Clock, typename _Duration>
    00093       bool
    00094       wait_until(unique_lock<mutex>& __lock,
    00095          const chrono::time_point<_Clock, _Duration>& __atime)
    00096       {
    00097     // DR 887 - Sync unknown clock to known clock.
    00098     typename _Clock::time_point __c_entry = _Clock::now();
    00099     __clock_t::time_point __s_entry = __clock_t::now();
    00100     chrono::nanoseconds __delta = __atime - __c_entry;
    00101     __clock_t::time_point __s_atime = __s_entry + __delta;
    00102
    00103     return __wait_until_impl(__lock, __s_atime);
    00104       }
    00105
    00106     template<typename _Clock, typename _Duration, typename _Predicate>
    00107       bool
    00108       wait_until(unique_lock<mutex>& __lock,
    00109          const chrono::time_point<_Clock, _Duration>& __atime,
    00110          _Predicate __p)
    00111       {
    00112     while (!__p())
    00113       if (!wait_until(__lock, __atime))
    00114         return __p();
    00115
    00116     return true;
    00117       }
    00118
    00119     template<typename _Rep, typename _Period>
    00120       bool
    00121       wait_for(unique_lock<mutex>& __lock,
    00122            const chrono::duration<_Rep, _Period>& __rtime)
    00123       { return wait_until(__lock, __clock_t::now() + __rtime); }
    00124
    00125     template<typename _Rep, typename _Period, typename _Predicate>
    00126       bool
    00127       wait_for(unique_lock<mutex>& __lock,
    00128            const chrono::duration<_Rep, _Period>& __rtime,
    00129            _Predicate __p)
    00130       { return wait_until(__lock, __clock_t::now() + __rtime, std::move(__p)); }
    00131
    00132     native_handle_type
    00133     native_handle()
    00134     { return &_M_cond; }
    00135
    00136   private:
    00137     template<typename _Clock, typename _Duration>
    00138       bool
    00139       __wait_until_impl(unique_lock<mutex>& __lock,
    00140             const chrono::time_point<_Clock, _Duration>& __atime)
    00141       {
    00142     chrono::time_point<__clock_t, chrono::seconds> __s =
    00143       chrono::time_point_cast<chrono::seconds>(__atime);
    00144
    00145     chrono::nanoseconds __ns =
    00146       chrono::duration_cast<chrono::nanoseconds>(__atime - __s);
    00147
    00148     __gthread_time_t __ts =
    00149       {
    00150         static_cast<std::time_t>(__s.time_since_epoch().count()),
    00151         static_cast<long>(__ns.count())
    00152       };
    00153
    00154     __gthread_cond_timedwait(&_M_cond, __lock.mutex()->native_handle(),
    00155                  &__ts);
    00156
    00157     return _Clock::now() < __atime;
    00158       }
    00159   };
    00160
    00161   /// condition_variable_any
    00162   // Like above, only mutex may not have try_lock.
    00163   class condition_variable_any
    00164   {
    00165     typedef __gthread_cond_t        __native_type;
    00166     __native_type           _M_cond;
    00167
    00168   public:
    00169     typedef __native_type*      native_handle_type;
    00170
    00171     condition_variable_any();
    00172     ~condition_variable_any();
    00173
    00174     condition_variable_any(const condition_variable_any&) = delete;
    00175     condition_variable_any& operator=(const condition_variable_any&) = delete;
    00176
    00177     void
    00178     notify_one();
    00179
    00180     void
    00181     notify_all();
    00182
    00183     template<typename _Lock>
    00184       void
    00185       wait(_Lock& __lock);
    00186
    00187     template<typename _Lock, typename _Predicate>
    00188       void
    00189       wait(_Lock& __lock, _Predicate __p);
    00190
    00191     template<typename _Lock, typename _Clock, typename _Duration>
    00192       bool
    00193       wait_until(_Lock& __lock,
    00194          const chrono::time_point<_Clock, _Duration>& __atime);
    00195
    00196     template<typename _Lock, typename _Clock,
    00197          typename _Duration, typename _Predicate>
    00198       bool
    00199       wait_until(_Lock& __lock,
    00200          const chrono::time_point<_Clock, _Duration>& __atime,
    00201          _Predicate __p);
    00202
    00203     template<typename _Lock, typename _Rep, typename _Period>
    00204       bool
    00205       wait_for(_Lock& __lock, const chrono::duration<_Rep, _Period>& __rtime);
    00206
    00207     template<typename _Lock, typename _Rep,
    00208          typename _Period, typename _Predicate>
    00209       bool
    00210       wait_for(_Lock& __lock,
    00211            const chrono::duration<_Rep, _Period>& __rtime, _Predicate __p);
    00212
    00213     native_handle_type
    00214     native_handle()
    00215     { return &_M_cond; }
    00216   };
    00217
    00218   // @} group condition_variables
    00219 }
    00220
    00221 #endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1
    00222
    00223 #endif // __GXX_EXPERIMENTAL_CXX0X__
    00224
    00225 #endif // _GLIBCXX_CONDITION_VARIABLE