libstdc++-v3/src/thread.cc

   1 // thread -*- C++ -*-
   2
   3 // Copyright (C) 2008, 2009, 2010, 2011 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 3, 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 // Under Section 7 of GPL version 3, you are granted additional
  17 // permissions described in the GCC Runtime Library Exception, version
  18 // 3.1, as published by the Free Software Foundation.
  19
  20 // You should have received a copy of the GNU General Public License and
  21 // a copy of the GCC Runtime Library Exception along with this program;
  22 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  23 // <http://www.gnu.org/licenses/>.
  24
  25
  26 #include <thread>
  27 #include <system_error>
  28 #include <cerrno>
  29
  30 #if defined(_GLIBCXX_USE_GET_NPROCS)
  31 # include <sys/sysinfo.h>
  32 # define _GLIBCXX_NPROCS get_nprocs()
  33 #elif defined(_GLIBCXX_USE_PTHREADS_NUM_PROCESSORS_NP)
  34 # define _GLIBCXX_NPROCS pthread_num_processors_np()
  35 #elif defined(_GLIBCXX_USE_SYSCTL_HW_NCPU)
  36 # include <stddef.h>
  37 # include <sys/sysctl.h>
  38 static inline int get_nprocs()
  39 {
  40  int count;
  41  size_t size = sizeof(count);
  42  int mib[] = { CTL_HW, HW_NCPU };
  43  if (!sysctl(mib, 2, &count, &size, NULL, 0))
  44    return count;
  45  return 0;
  46 }
  47 # define _GLIBCXX_NPROCS get_nprocs()
  48 #elif defined(_GLIBCXX_USE_SC_NPROCESSORS_ONLN)
  49 # include <unistd.h>
  50 # define _GLIBCXX_NPROCS sysconf(_SC_NPROCESSORS_ONLN)
  51 #elif defined(_GLIBCXX_USE_SC_NPROC_ONLN)
  52 # include <unistd.h>
  53 # define _GLIBCXX_NPROCS sysconf(_SC_NPROC_ONLN)
  54 #else
  55 # define _GLIBCXX_NPROCS 0
  56 #endif
  57
  58 #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
  59
  60 namespace std _GLIBCXX_VISIBILITY(default)
  61 {
  62   namespace
  63   {
  64     extern "C" void*
  65     execute_native_thread_routine(void* __p)
  66     {
  67       thread::_Impl_base* __t = static_cast<thread::_Impl_base*>(__p);
  68       thread::__shared_base_type __local;
  69       __local.swap(__t->_M_this_ptr);
  70
  71       __try
  72         {
  73           __t->_M_run();
  74         }
  75       __catch(...)
  76         {
  77           std::terminate();
  78         }
  79
  80       return 0;
  81     }
  82   }
  83
  84 _GLIBCXX_BEGIN_NAMESPACE_VERSION
  85
  86   void
  87   thread::join()
  88   {
  89     int __e = EINVAL;
  90
  91     if (_M_id != id())
  92       __e = __gthread_join(_M_id._M_thread, 0);
  93
  94     if (__e)
  95       __throw_system_error(__e);
  96
  97     _M_id = id();
  98   }
  99
 100   void
 101   thread::detach()
 102   {
 103     int __e = EINVAL;
 104
 105     if (_M_id != id())
 106       __e = __gthread_detach(_M_id._M_thread);
 107
 108     if (__e)
 109       __throw_system_error(__e);
 110
 111     _M_id = id();
 112   }
 113
 114   void
 115   thread::_M_start_thread(__shared_base_type __b)
 116   {
 117     if (!__gthread_active_p())
 118       __throw_system_error(int(errc::operation_not_permitted));
 119
 120     __b->_M_this_ptr = __b;
 121     int __e = __gthread_create(&_M_id._M_thread,
 122                                &execute_native_thread_routine, __b.get());
 123     if (__e)
 124     {
 125       __b->_M_this_ptr.reset();
 126       __throw_system_error(__e);
 127     }
 128   }
 129
 130   unsigned int
 131   thread::hardware_concurrency() noexcept
 132   {
 133     int __n = _GLIBCXX_NPROCS;
 134     if (__n < 0)
 135       __n = 0;
 136     return __n;
 137   }
 138
 139 _GLIBCXX_END_NAMESPACE_VERSION
 140 } // namespace std
 141
 142 #endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1