dust3d/thirdparty/cgal/CGAL-5.1/include/CGAL/thread.h

98 lines
2.5 KiB
C++

// Copyright (c) 2018 GeometryFactory Sarl (France).
// All rights reserved.
//
// This file is part of CGAL (www.cgal.org)
//
// $URL: https://github.com/CGAL/cgal/blob/v5.1/STL_Extension/include/CGAL/thread.h $
// $Id: thread.h 0779373 2020-03-26T13:31:46+01:00 Sébastien Loriot
// SPDX-License-Identifier: LGPL-3.0-or-later OR LicenseRef-Commercial
//
// Author(s) : Simon Giraudot
#ifndef CGAL_THREAD_H
#define CGAL_THREAD_H
#include <CGAL/config.h>
/*
This file defines the following:
- CGAL::cpp11::thread
- CGAL::cpp11::atomic
- CGAL::cpp11::sleep_for
It uses either TBB or STD depending on what's available: as TBB can
quite often override `std::thread`, it is possible that TBB will be
used instead of STD even if the real CXX11 `std::thread` is
available.
As the conflicting API between TBB and STD can be quite complicated,
we offer a more generic `sleep_for()` function that takes
double-typed seconds as argument and deals with it.
*/
#if defined(CGAL_LINKED_WITH_TBB)
# include <tbb/tbb_config.h>
# if TBB_IMPLEMENT_CPP0X
# include <tbb/compat/thread>
# include <atomic>
# include <tbb/tick_count.h>
# define CGAL_USE_TBB_THREADS 1
# else
# define CGAL_USE_TBB_THREADS 0
# endif
#else
# define CGAL_USE_TBB_THREADS 0
#endif
#if !CGAL_USE_TBB_THREADS
# include <thread>
# include <chrono>
#endif
#include <CGAL/atomic.h> // for CGAL::cpp11::atomic
namespace CGAL {
namespace cpp11 {
#if CGAL_USE_TBB_THREADS
using std::thread; // std::thread is declared by TBB if TBB_IMPLEMENT_CPP0X == 1
inline void sleep_for (double seconds)
{
// std::this_thread::sleep_for is declared by TBB if TBB_IMPLEMENT_CPP0X == 1
// It takes interval_t types as argument (!= from the std norm)
std::this_thread::sleep_for(tbb::tick_count::interval_t(seconds));
}
#else // C++11 implementation
using std::thread;
inline void sleep_for (double seconds)
{
// MSVC2013 cannot call `sleep_for()` with other types than
// std::chrono::nanoseconds (bug in the implementation of the norm).
typedef std::chrono::nanoseconds nanoseconds;
nanoseconds ns (nanoseconds::rep (1000000000.0 * seconds));
std::this_thread::sleep_for(ns);
}
#endif
#if defined(CGAL_NO_ATOMIC) && defined(CGAL_LINKED_WITH_TBB)
// If <CGAL/atomic.h> did not defined CGAL::cpp11::atomic, then use
// std::atomic as a fallback.
using std::atomic;
#endif
} // cpp11
} //namespace CGAL
#undef CGAL_USE_TBB_THREADS
#endif // CGAL_THREAD_H