mirror of
https://gcc.gnu.org/git/gcc.git
synced 2025-01-07 03:23:44 +08:00
306 lines
7.3 KiB
C++
306 lines
7.3 KiB
C++
// <thread> -*- C++ -*-
|
|
|
|
// Copyright (C) 2008-2021 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> // std::chrono::*
|
|
|
|
#if __cplusplus > 201703L
|
|
# include <compare> // std::strong_ordering
|
|
# include <stop_token> // std::stop_source, std::stop_token, std::nostopstate
|
|
#endif
|
|
|
|
#include <bits/std_thread.h> // std::thread, get_id, yield
|
|
|
|
#ifdef _GLIBCXX_USE_NANOSLEEP
|
|
# include <cerrno> // errno, EINTR
|
|
# include <time.h> // nanosleep
|
|
#endif
|
|
|
|
namespace std _GLIBCXX_VISIBILITY(default)
|
|
{
|
|
_GLIBCXX_BEGIN_NAMESPACE_VERSION
|
|
|
|
/**
|
|
* @defgroup threads Threads
|
|
* @ingroup concurrency
|
|
*
|
|
* Classes for thread support.
|
|
* @{
|
|
*/
|
|
|
|
// std::thread is defined in <bits/std_thread.h>
|
|
|
|
#if __cpp_lib_three_way_comparison
|
|
inline strong_ordering
|
|
operator<=>(thread::id __x, thread::id __y) noexcept
|
|
{ return __x._M_thread <=> __y._M_thread; }
|
|
#else
|
|
inline bool
|
|
operator!=(thread::id __x, thread::id __y) noexcept
|
|
{ return !(__x == __y); }
|
|
|
|
inline 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;
|
|
}
|
|
|
|
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); }
|
|
#endif // __cpp_lib_three_way_comparison
|
|
|
|
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;
|
|
}
|
|
|
|
/** @namespace std::this_thread
|
|
* @brief ISO C++ 2011 namespace for interacting with the current thread
|
|
*
|
|
* C++11 30.3.2 [thread.thread.this] Namespace this_thread.
|
|
*/
|
|
namespace this_thread
|
|
{
|
|
#ifndef _GLIBCXX_NO_SLEEP
|
|
|
|
#ifndef _GLIBCXX_USE_NANOSLEEP
|
|
void
|
|
__sleep_for(chrono::seconds, chrono::nanoseconds);
|
|
#endif
|
|
|
|
/// this_thread::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
|
|
struct ::timespec __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
|
|
}
|
|
|
|
/// this_thread::sleep_until
|
|
template<typename _Clock, typename _Duration>
|
|
inline void
|
|
sleep_until(const chrono::time_point<_Clock, _Duration>& __atime)
|
|
{
|
|
#if __cplusplus > 201703L
|
|
static_assert(chrono::is_clock_v<_Clock>);
|
|
#endif
|
|
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();
|
|
}
|
|
}
|
|
} // namespace this_thread
|
|
#endif // ! NO_SLEEP
|
|
|
|
#ifdef __cpp_lib_jthread
|
|
|
|
/// A thread that can be requested to stop and automatically joined.
|
|
class jthread
|
|
{
|
|
public:
|
|
using id = thread::id;
|
|
using native_handle_type = thread::native_handle_type;
|
|
|
|
jthread() noexcept
|
|
: _M_stop_source{nostopstate}
|
|
{ }
|
|
|
|
template<typename _Callable, typename... _Args,
|
|
typename = enable_if_t<!is_same_v<remove_cvref_t<_Callable>,
|
|
jthread>>>
|
|
explicit
|
|
jthread(_Callable&& __f, _Args&&... __args)
|
|
: _M_thread{_S_create(_M_stop_source, std::forward<_Callable>(__f),
|
|
std::forward<_Args>(__args)...)}
|
|
{ }
|
|
|
|
jthread(const jthread&) = delete;
|
|
jthread(jthread&&) noexcept = default;
|
|
|
|
~jthread()
|
|
{
|
|
if (joinable())
|
|
{
|
|
request_stop();
|
|
join();
|
|
}
|
|
}
|
|
|
|
jthread&
|
|
operator=(const jthread&) = delete;
|
|
|
|
jthread&
|
|
operator=(jthread&& __other) noexcept
|
|
{
|
|
std::jthread(std::move(__other)).swap(*this);
|
|
return *this;
|
|
}
|
|
|
|
void
|
|
swap(jthread& __other) noexcept
|
|
{
|
|
std::swap(_M_stop_source, __other._M_stop_source);
|
|
std::swap(_M_thread, __other._M_thread);
|
|
}
|
|
|
|
[[nodiscard]] bool
|
|
joinable() const noexcept
|
|
{
|
|
return _M_thread.joinable();
|
|
}
|
|
|
|
void
|
|
join()
|
|
{
|
|
_M_thread.join();
|
|
}
|
|
|
|
void
|
|
detach()
|
|
{
|
|
_M_thread.detach();
|
|
}
|
|
|
|
[[nodiscard]] id
|
|
get_id() const noexcept
|
|
{
|
|
return _M_thread.get_id();
|
|
}
|
|
|
|
[[nodiscard]] native_handle_type
|
|
native_handle()
|
|
{
|
|
return _M_thread.native_handle();
|
|
}
|
|
|
|
[[nodiscard]] static unsigned
|
|
hardware_concurrency() noexcept
|
|
{
|
|
return thread::hardware_concurrency();
|
|
}
|
|
|
|
[[nodiscard]] stop_source
|
|
get_stop_source() noexcept
|
|
{
|
|
return _M_stop_source;
|
|
}
|
|
|
|
[[nodiscard]] stop_token
|
|
get_stop_token() const noexcept
|
|
{
|
|
return _M_stop_source.get_token();
|
|
}
|
|
|
|
bool request_stop() noexcept
|
|
{
|
|
return _M_stop_source.request_stop();
|
|
}
|
|
|
|
friend void swap(jthread& __lhs, jthread& __rhs) noexcept
|
|
{
|
|
__lhs.swap(__rhs);
|
|
}
|
|
|
|
private:
|
|
template<typename _Callable, typename... _Args>
|
|
static thread
|
|
_S_create(stop_source& __ssrc, _Callable&& __f, _Args&&... __args)
|
|
{
|
|
if constexpr(is_invocable_v<decay_t<_Callable>, stop_token,
|
|
decay_t<_Args>...>)
|
|
return thread{std::forward<_Callable>(__f), __ssrc.get_token(),
|
|
std::forward<_Args>(__args)...};
|
|
else
|
|
{
|
|
static_assert(is_invocable_v<decay_t<_Callable>,
|
|
decay_t<_Args>...>,
|
|
"std::thread arguments must be invocable after"
|
|
" conversion to rvalues");
|
|
return thread{std::forward<_Callable>(__f),
|
|
std::forward<_Args>(__args)...};
|
|
}
|
|
}
|
|
|
|
stop_source _M_stop_source;
|
|
thread _M_thread;
|
|
};
|
|
#endif // __cpp_lib_jthread
|
|
|
|
// @} group threads
|
|
|
|
_GLIBCXX_END_NAMESPACE_VERSION
|
|
} // namespace
|
|
#endif // C++11
|
|
#endif // _GLIBCXX_THREAD
|