libmesh_singleton.C

Go to the documentation of this file.

// The libMesh Finite Element Library.
// Copyright (C) 2002-2019 Benjamin S. Kirk, John W. Peterson, Roy H. Stogner
 
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, 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
// Lesser General Public License for more details.
 
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 
 
 
// Local includes
#include "libmesh/libmesh_singleton.h"
#include "libmesh/threads.h"
#include "libmesh/simple_range.h"
 
// C/C++ includes
#include <vector>
 
 
// --------------------------------------------------------
// Local anonymous namespace to hold miscellaneous bits
namespace
{
using namespace libMesh;
 
// Mutex object for required locking
typedef Threads::spin_mutex SingletonMutex;
SingletonMutex singleton_mtx, setup_mtx;
 
// global list of runtime Singleton objects - created dynamically,
// cleaned up in reverse order.
typedef std::vector<Singleton *> SingletonList;
 
SingletonList & get_singleton_cache()
{
  static SingletonList singleton_cache;
  return singleton_cache;
}
 
typedef std::vector<Singleton::Setup *> SetupList;
SetupList & get_setup_cache()
{
  static SetupList setup_cache;
  return setup_cache;
}
 
} // end anonymous namespace
 
 
 
// --------------------------------------------------------
// Local anonymous namespace to hold miscellaneous bits
namespace libMesh
{
 
Singleton::Singleton ()
{
  SingletonMutex::scoped_lock lock(singleton_mtx);
 
  get_singleton_cache().push_back (this);
}
 
 
 
Singleton::Setup::Setup ()
{
  get_setup_cache().push_back (this);
}
 
 
 
void Singleton::setup ()
{
  SingletonMutex::scoped_lock lock(setup_mtx);
 
  SetupList & setup_cache = get_setup_cache();
 
  for (auto & item : setup_cache)
    {
      libmesh_assert (item);
      item->setup();
    }
}
 
 
 
void Singleton::cleanup ()
{
  SingletonMutex::scoped_lock lock(singleton_mtx);
 
  SingletonList & singleton_cache = get_singleton_cache();
 
  for (auto & item : as_range(singleton_cache.rbegin(),
                              singleton_cache.rend()))
    {
      libmesh_assert (item);
      delete item;
      item = nullptr;
    }
 
  singleton_cache.clear();
}
 
 
 
} // namespace libMesh