thread
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// <thread> -*- C++ -*-
// Copyright (C) 2008-2013 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 3, 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.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/** @file include/thread
* This is a Standard C++ Library header.
*/
#ifndef _GLIBCXX_THREAD
#define _GLIBCXX_THREAD 1
#pragma GCC system_header
#if __cplusplus < 201103L
# include <bits/c++0x_warning.h>
#else
#include <chrono>
#include <functional>
#include <memory>
#include <bits/functexcept.h>
#include <bits/functional_hash.h>
#include <bits/gthr.h>
#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/**
* @defgroup threads Threads
* @ingroup concurrency
*
* Classes for thread support.
* @{
*/
/// thread
class thread
{
public:
typedef __gthread_t native_handle_type;
struct _Impl_base;
typedef shared_ptr<_Impl_base> __shared_base_type;
/// thread::id
class id
{
native_handle_type _M_thread;
public:
id() noexcept : _M_thread() { }
explicit
id(native_handle_type __id) : _M_thread(__id) { }
private:
friend class thread;
friend class hash<thread::id>;
friend bool
operator==(thread::id __x, thread::id __y) noexcept
{ return __gthread_equal(__x._M_thread, __y._M_thread); }
friend bool
operator<(thread::id __x, thread::id __y) noexcept
{ return __x._M_thread < __y._M_thread; }
template<class _CharT, class _Traits>
friend basic_ostream<_CharT, _Traits>&
operator<<(basic_ostream<_CharT, _Traits>& __out, thread::id __id);
};
// Simple base type that the templatized, derived class containing
// an arbitrary functor can be converted to and called.
struct _Impl_base
{
__shared_base_type _M_this_ptr;
inline virtual ~_Impl_base();
virtual void _M_run() = 0;
};
template<typename _Callable>
struct _Impl : public _Impl_base
{
_Callable _M_func;
_Impl(_Callable&& __f) : _M_func(std::forward<_Callable>(__f))
{ }
void
_M_run() { _M_func(); }
};
private:
id _M_id;
public:
thread() noexcept = default;
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 2097. packaged_task constructors should be constrained
thread(thread&) = delete;
thread(const thread&) = delete;
thread(thread&& __t) noexcept
{ swap(__t); }
template<typename _Callable, typename... _Args>
explicit
thread(_Callable&& __f, _Args&&... __args)
{
_M_start_thread(_M_make_routine(std::__bind_simple(
std::forward<_Callable>(__f),
std::forward<_Args>(__args)...)));
}
~thread()
{
if (joinable())
std::terminate();
}
thread& operator=(const thread&) = delete;
thread& operator=(thread&& __t) noexcept
{
if (joinable())
std::terminate();
swap(__t);
return *this;
}
void
swap(thread& __t) noexcept
{ std::swap(_M_id, __t._M_id); }
bool
joinable() const noexcept
{ return !(_M_id == id()); }
void
join();
void
detach();
thread::id
get_id() const noexcept
{ return _M_id; }
/** @pre thread is joinable
*/
native_handle_type
native_handle()
{ return _M_id._M_thread; }
// Returns a value that hints at the number of hardware thread contexts.
static unsigned int
hardware_concurrency() noexcept;
private:
void
_M_start_thread(__shared_base_type);
template<typename _Callable>
shared_ptr<_Impl<_Callable>>
_M_make_routine(_Callable&& __f)
{
// Create and allocate full data structure, not base.
return std::make_shared<_Impl<_Callable>>(std::forward<_Callable>(__f));
}
};
inline thread::_Impl_base::~_Impl_base() = default;
inline void
swap(thread& __x, thread& __y) noexcept
{ __x.swap(__y); }
inline bool
operator!=(thread::id __x, thread::id __y) noexcept
{ return !(__x == __y); }
inline bool
operator<=(thread::id __x, thread::id __y) noexcept
{ return !(__y < __x); }
inline bool
operator>(thread::id __x, thread::id __y) noexcept
{ return __y < __x; }
inline bool
operator>=(thread::id __x, thread::id __y) noexcept
{ return !(__x < __y); }
// DR 889.
/// std::hash specialization for thread::id.
template<>
struct hash<thread::id>
: public __hash_base<size_t, thread::id>
{
size_t
operator()(const thread::id& __id) const noexcept
{ return std::_Hash_impl::hash(__id._M_thread); }
};
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 << "thread::id of a non-executing thread";
else
return __out << __id._M_thread;
}
_GLIBCXX_END_NAMESPACE_VERSION
/** @namespace std::this_thread
* @brief ISO C++ 2011 entities sub-namespace for thread.
* 30.3.2 Namespace this_thread.
*/
namespace this_thread
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/// get_id
inline thread::id
get_id() noexcept { return thread::id(__gthread_self()); }
/// yield
inline void
yield() noexcept
{
#ifdef _GLIBCXX_USE_SCHED_YIELD
__gthread_yield();
#endif
}
void
__sleep_for(chrono::seconds, chrono::nanoseconds);
/// sleep_for
template<typename _Rep, typename _Period>
inline void
sleep_for(const chrono::duration<_Rep, _Period>& __rtime)
{
auto __s = chrono::duration_cast<chrono::seconds>(__rtime);
auto __ns = chrono::duration_cast<chrono::nanoseconds>(__rtime - __s);
#ifdef _GLIBCXX_USE_NANOSLEEP
__gthread_time_t __ts =
{
static_cast<std::time_t>(__s.count()),
static_cast<long>(__ns.count())
};
::nanosleep(&__ts, 0);
#else
__sleep_for(__s, __ns);
#endif
}
/// sleep_until
template<typename _Clock, typename _Duration>
inline void
sleep_until(const chrono::time_point<_Clock, _Duration>& __atime)
{ sleep_for(__atime - _Clock::now()); }
_GLIBCXX_END_NAMESPACE_VERSION
}
// @} group threads
} // namespace
#endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1
#endif // C++11
#endif // _GLIBCXX_THREAD