gcc/libstdc++-v3/include/std/thread

// <thread> -*- C++ -*-

// Copyright (C) 2008, 2009 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2, or (at your option)
// any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this library; see the file COPYING.  If not, write to
// the Free Software Foundation, 51 Franklin Street, Fifth Floor,
// Boston, MA 02110-1301, USA.

// As a special exception, you may use this file as part of a free software
// library without restriction.  Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License.  This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.

/** @file thread
 *  This is a Standard C++ Library header.
 */

#ifndef _GLIBCXX_THREAD
#define _GLIBCXX_THREAD 1

#pragma GCC system_header

#ifndef __GXX_EXPERIMENTAL_CXX0X__
# include <c++0x_warning.h>
#else

#include <chrono>
#include <exception>
#include <functional>
#include <memory>
#include <mutex>
#include <condition_variable>
#include <type_traits>
#include <cstddef>
#include <bits/functexcept.h>
#include <bits/gthr.h>

#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)

namespace std
{
  class __thread_data_base;

  typedef shared_ptr<__thread_data_base> __thread_data_ptr;

  class __thread_data_base : public enable_shared_from_this<__thread_data_base>
  {
  public:
    __thread_data_base() = default;
    virtual ~__thread_data_base() = default;
    
    virtual void __run() = 0;
    
    __gthread_t 	_M_thread_handle;
    __thread_data_ptr 	_M_this_ptr;
    mutex 		_M_data_mutex;
  };
  
  template<typename _Callable>
    class __thread_data : public __thread_data_base
    {
    public:
      __thread_data(_Callable&& __f)
      : _M_func(std::forward<_Callable>(__f))
      { }

      void __run()
      { _M_func(); }

    private:
      _Callable _M_func;
    };

  /// thread
  class thread
  {
  public:
    // types
    class id;
    typedef __gthread_t native_handle_type;

    // cons
    thread() = default;
    
    template<typename _Callable>
      explicit thread(_Callable __f)
      : _M_thread_data(__make_thread_data(__f))
      { __start_thread(); }

    template<typename _Callable, typename... _Args>
      thread(_Callable&& __f, _Args&&... __args)
      : _M_thread_data(__make_thread_data(std::bind(__f, __args...)))
      { __start_thread(); }

    ~thread()
    { detach(); }

    thread(const thread&) = delete;
    thread(thread&&);
    thread& operator=(const thread&) = delete;
    thread& operator=(thread&&);

    // members
    void 
    swap(thread&& __t)
    { std::swap(_M_thread_data, __t._M_thread_data); }

    bool 
    joinable() const;

    void 
    join();

    void 
    detach();

    thread::id
    get_id() const;

    native_handle_type 
    native_handle()
    { return _M_thread_data->_M_thread_handle; }

    // static members
    static unsigned hardware_concurrency();

    __thread_data_ptr
    _M_get_thread_data() const
    {
      lock_guard<mutex> __l(_M_thread_data_mutex);
      return _M_thread_data;
    }

  private:
    template<typename _Callable>
      __thread_data_ptr 
      __make_thread_data(_Callable&& __f)
      { 
	return __thread_data_ptr(
	  new __thread_data<_Callable>(std::forward<_Callable>(__f)));
      }
    
    __thread_data_ptr
    __make_thread_data(void(*__f)())
    { return __thread_data_ptr(new __thread_data<void(*)()>(__f)); }
    
    void __start_thread();

    __thread_data_ptr 	_M_thread_data;
    mutable mutex 	_M_thread_data_mutex;
  };

  inline void
  swap(thread& __x, thread& __y)
  { __x.swap(__y); }

  inline void
  swap(thread&& __x, thread& __y)
  { __x.swap(__y); }
  
  inline void
  swap(thread& __x, thread&& __y)
  { __x.swap(__y); }

  namespace this_thread
  {
    thread::id
    get_id();

#ifdef _GLIBCXX_USE_SCHED_YIELD
    inline void
    yield()
    { __gthread_yield(); }
#endif

#ifdef _GLIBCXX_USE_NANOSLEEP
    template<typename _Clock, typename _Duration>
      inline void
      sleep_until(const chrono::time_point<_Clock, _Duration>& __atime)
      { sleep_for(__atime - _Clock::now()); }

    template<typename _Rep, typename _Period>
      inline void
      sleep_for(const chrono::duration<_Rep, _Period>& __rtime)
      {
	chrono::seconds __s =
	  chrono::duration_cast<chrono::seconds>(__rtime);

	chrono::nanoseconds __ns =
	  chrono::duration_cast<chrono::nanoseconds>(__rtime - __s);

	__gthread_time_t __ts = 
	  {
	    static_cast<std::time_t>(__s.count()),
	    static_cast<long>(__ns.count())
	  };

	::nanosleep(&__ts, 0);
      }
#endif
  }

  /// thread::id
  class thread::id
  {
  public:
    id() : _M_thread_id() { }

  private:
    friend class thread;

    friend thread::id this_thread::get_id();

    friend bool 
    operator==(thread::id __x, thread::id __y)
    { return static_cast<bool>(__gthread_equal(__x._M_thread_id,
					       __y._M_thread_id)); }

    friend bool
    operator<(thread::id __x, thread::id __y)
    { return __x._M_thread_id < __y._M_thread_id; }

    template<class _CharT, class _Traits>
      friend basic_ostream<_CharT, _Traits>&
      operator<<(basic_ostream<_CharT, _Traits>&& __out, thread::id __id); 

    id(__gthread_t __id)
    : _M_thread_id(__id)
    { }
      
    __gthread_t _M_thread_id;
  };

  inline bool
  operator!=(thread::id __x, thread::id __y)
  { return !(__x == __y); }
  
  inline bool
  operator<=(thread::id __x, thread::id __y)
  { return !(__y < __x); }
  
  inline bool
  operator>(thread::id __x, thread::id __y)
  { return __y < __x; }
  
  inline bool
  operator>=(thread::id __x, thread::id __y)
  { return !(__x < __y); }
  
  template<class _CharT, class _Traits>
    inline basic_ostream<_CharT, _Traits>&
    operator<<(basic_ostream<_CharT, _Traits>&& __out, thread::id __id)
    {
      if(__id == thread::id())
	return __out << "non-executing thread";
      else
	return __out << __id._M_thread_id;
    }  

  inline bool
  thread::joinable() const
  { return get_id() != thread::id(); }

  inline thread::id
  thread::get_id() const
  {
    if(_M_thread_data)
      return thread::id(_M_thread_data->_M_thread_handle);
    else
      return thread::id();
  }

  namespace this_thread
  {
    inline thread::id
    get_id()
    { return thread::id(__gthread_self()); }
  }
}

#endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1

#endif // __GXX_EXPERIMENTAL_CXX0X__

#endif // _GLIBCXX_THREAD