boost/signals2/detail/scope_guard.hpp

/* Copyright 2003-2013 Joaquin M Lopez Munoz.
 *           2019 Mike Dev <mike.dev@gmx.de>
 * Distributed under the Boost Software License, Version 1.0.
 * (See accompanying file LICENSE_1_0.txt or copy at
 * https://www.boost.org/LICENSE_1_0.txt)
 *
 * NOTE: internalized from Boost.MultiIndex
 *
 */


#ifndef BOOST_SIGNALS2_DETAIL_SCOPE_GUARD_HPP
#define BOOST_SIGNALS2_DETAIL_SCOPE_GUARD_HPP

#if defined(_MSC_VER)
#pragma once
#endif

#include <boost/core/no_exceptions_support.hpp>

namespace boost{

namespace signals2{

namespace detail{

/* This is a merely reformated version of
 * ScopeGuard.h as defined in:
 *   Alexandrescu, A., Marginean, P.:"Generic<Programming>: Change the Way You
 *     Write Exception-Safe Code - Forever", C/C++ Users Jornal, Dec 2000,
 *     http://www.drdobbs.com/184403758
 * with the following modifications:
 *   - General pretty formatting (pretty to my taste at least.)
 *   - Naming style changed to standard C++ library requirements.
 *   - Removed RefHolder and ByRef, whose functionality is provided
 *     already by Boost.Ref.
 *   - Removed static make_guard's and make_obj_guard's, so that the code
 *     will work even if BOOST_NO_MEMBER_TEMPLATES is defined. This forces
 *     us to move some private ctors to public, though.
 *
 * NB: CodeWarrior Pro 8 seems to have problems looking up safe_execute
 * without an explicit qualification.
 *
 *  TODO: Consider replacing with Boost.ScopeExit
 *
 */

class scope_guard_impl_base
{
public:
  scope_guard_impl_base():dismissed_(false){}
  void dismiss()const{dismissed_=true;}

protected:
  ~scope_guard_impl_base(){}

  scope_guard_impl_base(const scope_guard_impl_base& other):
    dismissed_(other.dismissed_)
  {
    other.dismiss();
  }

  template<typename J>
  static void safe_execute(J& j){
    BOOST_TRY{
      if(!j.dismissed_)j.execute();
    }
    BOOST_CATCH(...){}
    BOOST_CATCH_END
  }

  mutable bool dismissed_;

private:
  scope_guard_impl_base& operator=(const scope_guard_impl_base&);
};

typedef const scope_guard_impl_base& scope_guard;

template<class Obj,typename MemFun,typename P1,typename P2>
class obj_scope_guard_impl2:public scope_guard_impl_base
{
public:
  obj_scope_guard_impl2(Obj& obj,MemFun mem_fun,P1 p1,P2 p2):
    obj_(obj),mem_fun_(mem_fun),p1_(p1),p2_(p2)
  {}
  ~obj_scope_guard_impl2(){scope_guard_impl_base::safe_execute(*this);}
  void execute(){(obj_.*mem_fun_)(p1_,p2_);}

protected:
  Obj&     obj_;
  MemFun   mem_fun_;
  const P1 p1_;
  const P2 p2_;
};

template<class Obj,typename MemFun,typename P1,typename P2>
inline obj_scope_guard_impl2<Obj,MemFun,P1,P2>
make_obj_guard(Obj& obj,MemFun mem_fun,P1 p1,P2 p2)
{
  return obj_scope_guard_impl2<Obj,MemFun,P1,P2>(obj,mem_fun,p1,p2);
}

} /* namespace signals2::detail */

} /* namespace signals2 */

} /* namespace boost */

#endif
Boost C++ Libraries

boost/signals2/detail/scope_guard.hpp
