libstdc++-v3/src/c++11/thread.cc

   1 // thread -*- C++ -*-
   2
   3 // Copyright (C) 2008-2013 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 #include <cxxabi_forced.h>
  30
  31 #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
  32
  33 #if defined(_GLIBCXX_USE_GET_NPROCS)
  34 # include <sys/sysinfo.h>
  35 # define _GLIBCXX_NPROCS get_nprocs()
  36 #elif defined(_GLIBCXX_USE_PTHREADS_NUM_PROCESSORS_NP)
  37 # define _GLIBCXX_NPROCS pthread_num_processors_np()
  38 #elif defined(_GLIBCXX_USE_SYSCTL_HW_NCPU)
  39 # include <stddef.h>
  40 # include <sys/sysctl.h>
  41 static inline int get_nprocs()
  42 {
  43  int count;
  44  size_t size = sizeof(count);
  45  int mib[] = { CTL_HW, HW_NCPU };
  46  if (!sysctl(mib, 2, &count, &size, NULL, 0))
  47    return count;
  48  return 0;
  49 }
  50 # define _GLIBCXX_NPROCS get_nprocs()
  51 #elif defined(_GLIBCXX_USE_SC_NPROCESSORS_ONLN)
  52 # include <unistd.h>
  53 # define _GLIBCXX_NPROCS sysconf(_SC_NPROCESSORS_ONLN)
  54 #elif defined(_GLIBCXX_USE_SC_NPROC_ONLN)
  55 # include <unistd.h>
  56 # define _GLIBCXX_NPROCS sysconf(_SC_NPROC_ONLN)
  57 #else
  58 # define _GLIBCXX_NPROCS 0
  59 #endif
  60
  61 #ifndef _GLIBCXX_USE_NANOSLEEP
  62 # ifdef _GLIBCXX_HAVE_SLEEP
  63 #  include <unistd.h>
  64 # elif defined(_GLIBCXX_HAVE_WIN32_SLEEP)
  65 #  include <windows.h>
  66 # else
  67 #  error "No sleep function known for this target"
  68 # endif
  69 #endif
  70
  71 namespace std _GLIBCXX_VISIBILITY(default)
  72 {
  73   namespace
  74   {
  75     extern "C" void*
  76     execute_native_thread_routine(void* __p)
  77     {
  78       thread::_Impl_base* __t = static_cast<thread::_Impl_base*>(__p);
  79       thread::__shared_base_type __local;
  80       __local.swap(__t->_M_this_ptr);
  81
  82       __try
  83         {
  84           __t->_M_run();
  85         }
  86       __catch(const __cxxabiv1::__forced_unwind&)
  87         {
  88           __throw_exception_again;
  89         }
  90       __catch(...)
  91         {
  92           std::terminate();
  93         }
  94
  95       return 0;
  96     }
  97   }
  98
  99 _GLIBCXX_BEGIN_NAMESPACE_VERSION
 100
 101   void
 102   thread::join()
 103   {
 104     int __e = EINVAL;
 105
 106     if (_M_id != id())
 107       __e = __gthread_join(_M_id._M_thread, 0);
 108
 109     if (__e)
 110       __throw_system_error(__e);
 111
 112     _M_id = id();
 113   }
 114
 115   void
 116   thread::detach()
 117   {
 118     int __e = EINVAL;
 119
 120     if (_M_id != id())
 121       __e = __gthread_detach(_M_id._M_thread);
 122
 123     if (__e)
 124       __throw_system_error(__e);
 125
 126     _M_id = id();
 127   }
 128
 129   void
 130   thread::_M_start_thread(__shared_base_type __b)
 131   {
 132     if (!__gthread_active_p())
 133 #if __EXCEPTIONS
 134       throw system_error(make_error_code(errc::operation_not_permitted),
 135                          "Enable multithreading to use std::thread");
 136 #else
 137       __throw_system_error(int(errc::operation_not_permitted));
 138 #endif
 139
 140     __b->_M_this_ptr = __b;
 141     int __e = __gthread_create(&_M_id._M_thread,
 142                                &execute_native_thread_routine, __b.get());
 143     if (__e)
 144     {
 145       __b->_M_this_ptr.reset();
 146       __throw_system_error(__e);
 147     }
 148   }
 149
 150   unsigned int
 151   thread::hardware_concurrency() noexcept
 152   {
 153     int __n = _GLIBCXX_NPROCS;
 154     if (__n < 0)
 155       __n = 0;
 156     return __n;
 157   }
 158
 159 _GLIBCXX_END_NAMESPACE_VERSION
 160
 161 namespace this_thread
 162 {
 163 _GLIBCXX_BEGIN_NAMESPACE_VERSION
 164
 165   void
 166   __sleep_for(chrono::seconds __s, chrono::nanoseconds __ns)
 167   {
 168 #ifdef _GLIBCXX_USE_NANOSLEEP
 169     __gthread_time_t __ts =
 170       {
 171         static_cast<std::time_t>(__s.count()),
 172         static_cast<long>(__ns.count())
 173       };
 174     ::nanosleep(&__ts, 0);
 175 #elif defined(_GLIBCXX_HAVE_SLEEP)
 176 # ifdef _GLIBCXX_HAVE_USLEEP
 177     ::sleep(__s.count());
 178     if (__ns.count() > 0)
 179       {
 180         long __us = __ns.count() / 1000;
 181         if (__us == 0)
 182           __us = 1;
 183         ::usleep(__us);
 184       }
 185 # else
 186     ::sleep(__s.count() + (__ns >= 1000000));
 187 # endif
 188 #elif defined(_GLIBCXX_HAVE_WIN32_SLEEP)
 189     unsigned long ms = __ns.count() / 1000000;
 190     if (__ns.count() > 0 && ms == 0)
 191       ms = 1;
 192     ::Sleep(chrono::milliseconds(__s).count() + ms);
 193 #endif
 194   }
 195
 196 _GLIBCXX_END_NAMESPACE_VERSION
 197 }
 198
 199 } // namespace std
 200
 201 #endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1