360 lines
8.5 KiB
C++
360 lines
8.5 KiB
C++
// <thread> -*- C++ -*-
|
|
|
|
// Copyright (C) 2008-2016 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 <cerrno>
|
|
#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:
|
|
// Abstract base class for types that wrap arbitrary functors to be
|
|
// invoked in the new thread of execution.
|
|
struct _State
|
|
{
|
|
virtual ~_State();
|
|
virtual void _M_run() = 0;
|
|
};
|
|
using _State_ptr = unique_ptr<_State>;
|
|
|
|
typedef __gthread_t native_handle_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
|
|
{
|
|
// pthread_equal is undefined if either thread ID is not valid, so we
|
|
// can't safely use __gthread_equal on default-constructed values (nor
|
|
// the non-zero value returned by this_thread::get_id() for
|
|
// single-threaded programs using GNU libc). Assume EqualityComparable.
|
|
return __x._M_thread == __y._M_thread;
|
|
}
|
|
|
|
friend bool
|
|
operator<(thread::id __x, thread::id __y) noexcept
|
|
{
|
|
// Pthreads doesn't define any way to do this, so we just have to
|
|
// assume native_handle_type is LessThanComparable.
|
|
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);
|
|
};
|
|
|
|
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)
|
|
{
|
|
#ifdef GTHR_ACTIVE_PROXY
|
|
// Create a reference to pthread_create, not just the gthr weak symbol.
|
|
auto __depend = reinterpret_cast<void(*)()>(&pthread_create);
|
|
#else
|
|
auto __depend = nullptr;
|
|
#endif
|
|
_M_start_thread(_S_make_state(
|
|
std::__bind_simple(std::forward<_Callable>(__f),
|
|
std::forward<_Args>(__args)...)),
|
|
__depend);
|
|
}
|
|
|
|
~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:
|
|
template<typename _Callable>
|
|
struct _State_impl : public _State
|
|
{
|
|
_Callable _M_func;
|
|
|
|
_State_impl(_Callable&& __f) : _M_func(std::forward<_Callable>(__f))
|
|
{ }
|
|
|
|
void
|
|
_M_run() { _M_func(); }
|
|
};
|
|
|
|
void
|
|
_M_start_thread(_State_ptr, void (*)());
|
|
|
|
template<typename _Callable>
|
|
static _State_ptr
|
|
_S_make_state(_Callable&& __f)
|
|
{
|
|
using _Impl = _State_impl<_Callable>;
|
|
return _State_ptr{new _Impl{std::forward<_Callable>(__f)}};
|
|
}
|
|
#if _GLIBCXX_THREAD_ABI_COMPAT
|
|
public:
|
|
struct _Impl_base;
|
|
typedef shared_ptr<_Impl_base> __shared_base_type;
|
|
struct _Impl_base
|
|
{
|
|
__shared_base_type _M_this_ptr;
|
|
virtual ~_Impl_base() = default;
|
|
virtual void _M_run() = 0;
|
|
};
|
|
|
|
private:
|
|
void
|
|
_M_start_thread(__shared_base_type, void (*)());
|
|
|
|
void
|
|
_M_start_thread(__shared_base_type);
|
|
#endif
|
|
};
|
|
|
|
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
|
|
{
|
|
#ifdef __GLIBC__
|
|
// For the GNU C library pthread_self() is usable without linking to
|
|
// libpthread.so but returns 0, so we cannot use it in single-threaded
|
|
// programs, because this_thread::get_id() != thread::id{} must be true.
|
|
// We know that pthread_t is an integral type in the GNU C library.
|
|
if (!__gthread_active_p())
|
|
return thread::id(1);
|
|
#endif
|
|
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)
|
|
{
|
|
if (__rtime <= __rtime.zero())
|
|
return;
|
|
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())
|
|
};
|
|
while (::nanosleep(&__ts, &__ts) == -1 && errno == EINTR)
|
|
{ }
|
|
#else
|
|
__sleep_for(__s, __ns);
|
|
#endif
|
|
}
|
|
|
|
/// sleep_until
|
|
template<typename _Clock, typename _Duration>
|
|
inline void
|
|
sleep_until(const chrono::time_point<_Clock, _Duration>& __atime)
|
|
{
|
|
auto __now = _Clock::now();
|
|
if (_Clock::is_steady)
|
|
{
|
|
if (__now < __atime)
|
|
sleep_for(__atime - __now);
|
|
return;
|
|
}
|
|
while (__now < __atime)
|
|
{
|
|
sleep_for(__atime - __now);
|
|
__now = _Clock::now();
|
|
}
|
|
}
|
|
|
|
_GLIBCXX_END_NAMESPACE_VERSION
|
|
}
|
|
|
|
// @} group threads
|
|
|
|
} // namespace
|
|
|
|
#endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1
|
|
|
|
#endif // C++11
|
|
|
|
#endif // _GLIBCXX_THREAD
|