Chris@16: /* Copyright 2003-2013 Joaquin M Lopez Munoz.
Chris@16:  * Distributed under the Boost Software License, Version 1.0.
Chris@16:  * (See accompanying file LICENSE_1_0.txt or copy at
Chris@16:  * http://www.boost.org/LICENSE_1_0.txt)
Chris@16:  *
Chris@16:  * See http://www.boost.org/libs/multi_index for library home page.
Chris@16:  */
Chris@16: 
Chris@16: #ifndef BOOST_MULTI_INDEX_DETAIL_SCOPE_GUARD_HPP
Chris@16: #define BOOST_MULTI_INDEX_DETAIL_SCOPE_GUARD_HPP
Chris@16: 
Chris@101: #if defined(_MSC_VER)
Chris@16: #pragma once
Chris@16: #endif
Chris@16: 
Chris@16: #include <boost/detail/no_exceptions_support.hpp>
Chris@16: #include <boost/mpl/if.hpp>
Chris@16: 
Chris@16: namespace boost{
Chris@16: 
Chris@16: namespace multi_index{
Chris@16: 
Chris@16: namespace detail{
Chris@16: 
Chris@16: /* Until some official version of the ScopeGuard idiom makes it into Boost,
Chris@16:  * we locally define our own. This is a merely reformated version of
Chris@16:  * ScopeGuard.h as defined in:
Chris@16:  *   Alexandrescu, A., Marginean, P.:"Generic<Programming>: Change the Way You
Chris@16:  *     Write Exception-Safe Code - Forever", C/C++ Users Jornal, Dec 2000,
Chris@16:  *     http://www.drdobbs.com/184403758
Chris@16:  * with the following modifications:
Chris@16:  *   - General pretty formatting (pretty to my taste at least.)
Chris@16:  *   - Naming style changed to standard C++ library requirements.
Chris@16:  *   - Added scope_guard_impl4 and obj_scope_guard_impl3, (Boost.MultiIndex
Chris@16:  *     needs them). A better design would provide guards for many more
Chris@16:  *     arguments through the Boost Preprocessor Library.
Chris@16:  *   - Added scope_guard_impl_base::touch (see below.)
Chris@16:  *   - Removed RefHolder and ByRef, whose functionality is provided
Chris@16:  *     already by Boost.Ref.
Chris@16:  *   - Removed static make_guard's and make_obj_guard's, so that the code
Chris@16:  *     will work even if BOOST_NO_MEMBER_TEMPLATES is defined. This forces
Chris@16:  *     us to move some private ctors to public, though.
Chris@16:  *
Chris@16:  * NB: CodeWarrior Pro 8 seems to have problems looking up safe_execute
Chris@16:  * without an explicit qualification.
Chris@16:  * 
Chris@16:  * We also define the following variants of the idiom:
Chris@16:  * 
Chris@16:  *   - make_guard_if_c<bool>( ... )
Chris@16:  *   - make_guard_if<IntegralConstant>( ... )
Chris@16:  *   - make_obj_guard_if_c<bool>( ... )
Chris@16:  *   - make_obj_guard_if<IntegralConstant>( ... )
Chris@16:  * which may be used with a compile-time constant to yield
Chris@16:  * a "null_guard" if the boolean compile-time parameter is false,
Chris@16:  * or conversely, the guard is only constructed if the constant is true.
Chris@16:  * This is useful to avoid extra tagging, because the returned
Chris@16:  * null_guard can be optimzed comlpetely away by the compiler.
Chris@16:  */
Chris@16: 
Chris@16: class scope_guard_impl_base
Chris@16: {
Chris@16: public:
Chris@16:   scope_guard_impl_base():dismissed_(false){}
Chris@16:   void dismiss()const{dismissed_=true;}
Chris@16: 
Chris@16:   /* This helps prevent some "unused variable" warnings under, for instance,
Chris@16:    * GCC 3.2.
Chris@16:    */
Chris@16:   void touch()const{}
Chris@16: 
Chris@16: protected:
Chris@16:   ~scope_guard_impl_base(){}
Chris@16: 
Chris@16:   scope_guard_impl_base(const scope_guard_impl_base& other):
Chris@16:     dismissed_(other.dismissed_)
Chris@16:   {
Chris@16:     other.dismiss();
Chris@16:   }
Chris@16: 
Chris@16:   template<typename J>
Chris@16:   static void safe_execute(J& j){
Chris@16:     BOOST_TRY{
Chris@16:       if(!j.dismissed_)j.execute();
Chris@16:     }
Chris@16:     BOOST_CATCH(...){}
Chris@16:     BOOST_CATCH_END
Chris@16:   }
Chris@16:   
Chris@16:   mutable bool dismissed_;
Chris@16: 
Chris@16: private:
Chris@16:   scope_guard_impl_base& operator=(const scope_guard_impl_base&);
Chris@16: };
Chris@16: 
Chris@16: typedef const scope_guard_impl_base& scope_guard;
Chris@16: 
Chris@16: struct null_guard : public scope_guard_impl_base
Chris@16: {
Chris@16:     template< class T1 >
Chris@16:     null_guard( const T1& )
Chris@16:     { }
Chris@16: 
Chris@16:     template< class T1, class T2 >
Chris@16:     null_guard( const T1&, const T2& )
Chris@16:     { }
Chris@16: 
Chris@16:     template< class T1, class T2, class T3 >
Chris@16:     null_guard( const T1&, const T2&, const T3& )
Chris@16:     { }
Chris@16: 
Chris@16:     template< class T1, class T2, class T3, class T4 >
Chris@16:     null_guard( const T1&, const T2&, const T3&, const T4& )
Chris@16:     { }
Chris@16: 
Chris@16:     template< class T1, class T2, class T3, class T4, class T5 >
Chris@16:     null_guard( const T1&, const T2&, const T3&, const T4&, const T5& )
Chris@16:     { }
Chris@16: };
Chris@16: 
Chris@16: template< bool cond, class T >
Chris@16: struct null_guard_return
Chris@16: {
Chris@16:     typedef typename boost::mpl::if_c<cond,T,null_guard>::type type;
Chris@16: };
Chris@16: 
Chris@16: template<typename F>
Chris@16: class scope_guard_impl0:public scope_guard_impl_base
Chris@16: {
Chris@16: public:
Chris@16:   scope_guard_impl0(F fun):fun_(fun){}
Chris@16:   ~scope_guard_impl0(){scope_guard_impl_base::safe_execute(*this);}
Chris@16:   void execute(){fun_();}
Chris@16: 
Chris@16: protected:
Chris@16: 
Chris@16:   F fun_;
Chris@16: };
Chris@16: 
Chris@16: template<typename F> 
Chris@16: inline scope_guard_impl0<F> make_guard(F fun)
Chris@16: {
Chris@16:   return scope_guard_impl0<F>(fun);
Chris@16: }
Chris@16: 
Chris@16: template<bool cond, typename F> 
Chris@16: inline typename null_guard_return<cond,scope_guard_impl0<F> >::type  
Chris@16: make_guard_if_c(F fun)
Chris@16: {
Chris@16:   return typename null_guard_return<cond,scope_guard_impl0<F> >::type(fun);
Chris@16: }
Chris@16: 
Chris@16: template<typename C, typename F> 
Chris@16: inline typename null_guard_return<C::value,scope_guard_impl0<F> >::type  
Chris@16: make_guard_if(F fun)
Chris@16: {
Chris@16:   return make_guard_if<C::value>(fun);
Chris@16: }
Chris@16: 
Chris@16: template<typename F,typename P1>
Chris@16: class scope_guard_impl1:public scope_guard_impl_base
Chris@16: {
Chris@16: public:
Chris@16:   scope_guard_impl1(F fun,P1 p1):fun_(fun),p1_(p1){}
Chris@16:   ~scope_guard_impl1(){scope_guard_impl_base::safe_execute(*this);}
Chris@16:   void execute(){fun_(p1_);}
Chris@16: 
Chris@16: protected:
Chris@16:   F        fun_;
Chris@16:   const P1 p1_;
Chris@16: };
Chris@16: 
Chris@16: template<typename F,typename P1> 
Chris@16: inline scope_guard_impl1<F,P1> make_guard(F fun,P1 p1)
Chris@16: {
Chris@16:   return scope_guard_impl1<F,P1>(fun,p1);
Chris@16: }
Chris@16: 
Chris@16: template<bool cond, typename F,typename P1> 
Chris@16: inline typename null_guard_return<cond,scope_guard_impl1<F,P1> >::type 
Chris@16: make_guard_if_c(F fun,P1 p1)
Chris@16: {
Chris@16:   return typename null_guard_return<cond,scope_guard_impl1<F,P1> >::type(fun,p1);
Chris@16: }
Chris@16: 
Chris@16: template<typename C, typename F,typename P1> 
Chris@16: inline typename null_guard_return<C::value,scope_guard_impl1<F,P1> >::type 
Chris@16: make_guard_if(F fun,P1 p1)
Chris@16: {
Chris@16:   return make_guard_if_c<C::value>(fun,p1);
Chris@16: }
Chris@16: 
Chris@16: template<typename F,typename P1,typename P2>
Chris@16: class scope_guard_impl2:public scope_guard_impl_base
Chris@16: {
Chris@16: public:
Chris@16:   scope_guard_impl2(F fun,P1 p1,P2 p2):fun_(fun),p1_(p1),p2_(p2){}
Chris@16:   ~scope_guard_impl2(){scope_guard_impl_base::safe_execute(*this);}
Chris@16:   void execute(){fun_(p1_,p2_);}
Chris@16: 
Chris@16: protected:
Chris@16:   F        fun_;
Chris@16:   const P1 p1_;
Chris@16:   const P2 p2_;
Chris@16: };
Chris@16: 
Chris@16: template<typename F,typename P1,typename P2>
Chris@16: inline scope_guard_impl2<F,P1,P2> make_guard(F fun,P1 p1,P2 p2)
Chris@16: {
Chris@16:   return scope_guard_impl2<F,P1,P2>(fun,p1,p2);
Chris@16: }
Chris@16: 
Chris@16: template<bool cond, typename F,typename P1,typename P2>
Chris@16: inline typename null_guard_return<cond,scope_guard_impl2<F,P1,P2> >::type
Chris@16: make_guard_if_c(F fun,P1 p1,P2 p2)
Chris@16: {
Chris@16:   return typename null_guard_return<cond,scope_guard_impl2<F,P1,P2> >::type(fun,p1,p2);
Chris@16: }
Chris@16: 
Chris@16: template<typename C, typename F,typename P1,typename P2>
Chris@16: inline typename null_guard_return<C::value,scope_guard_impl2<F,P1,P2> >::type
Chris@16: make_guard_if(F fun,P1 p1,P2 p2)
Chris@16: {
Chris@16:   return make_guard_if_c<C::value>(fun,p1,p2);
Chris@16: }
Chris@16: 
Chris@16: template<typename F,typename P1,typename P2,typename P3>
Chris@16: class scope_guard_impl3:public scope_guard_impl_base
Chris@16: {
Chris@16: public:
Chris@16:   scope_guard_impl3(F fun,P1 p1,P2 p2,P3 p3):fun_(fun),p1_(p1),p2_(p2),p3_(p3){}
Chris@16:   ~scope_guard_impl3(){scope_guard_impl_base::safe_execute(*this);}
Chris@16:   void execute(){fun_(p1_,p2_,p3_);}
Chris@16: 
Chris@16: protected:
Chris@16:   F        fun_;
Chris@16:   const P1 p1_;
Chris@16:   const P2 p2_;
Chris@16:   const P3 p3_;
Chris@16: };
Chris@16: 
Chris@16: template<typename F,typename P1,typename P2,typename P3>
Chris@16: inline scope_guard_impl3<F,P1,P2,P3> make_guard(F fun,P1 p1,P2 p2,P3 p3)
Chris@16: {
Chris@16:   return scope_guard_impl3<F,P1,P2,P3>(fun,p1,p2,p3);
Chris@16: }
Chris@16: 
Chris@16: template<bool cond,typename F,typename P1,typename P2,typename P3>
Chris@16: inline typename null_guard_return<cond,scope_guard_impl3<F,P1,P2,P3> >::type 
Chris@16: make_guard_if_c(F fun,P1 p1,P2 p2,P3 p3)
Chris@16: {
Chris@16:   return typename null_guard_return<cond,scope_guard_impl3<F,P1,P2,P3> >::type(fun,p1,p2,p3);
Chris@16: }
Chris@16: 
Chris@16: template<typename C,typename F,typename P1,typename P2,typename P3>
Chris@16: inline typename null_guard_return< C::value,scope_guard_impl3<F,P1,P2,P3> >::type 
Chris@16: make_guard_if(F fun,P1 p1,P2 p2,P3 p3)
Chris@16: {
Chris@16:   return make_guard_if_c<C::value>(fun,p1,p2,p3);
Chris@16: }
Chris@16: 
Chris@16: template<typename F,typename P1,typename P2,typename P3,typename P4>
Chris@16: class scope_guard_impl4:public scope_guard_impl_base
Chris@16: {
Chris@16: public:
Chris@16:   scope_guard_impl4(F fun,P1 p1,P2 p2,P3 p3,P4 p4):
Chris@16:     fun_(fun),p1_(p1),p2_(p2),p3_(p3),p4_(p4){}
Chris@16:   ~scope_guard_impl4(){scope_guard_impl_base::safe_execute(*this);}
Chris@16:   void execute(){fun_(p1_,p2_,p3_,p4_);}
Chris@16: 
Chris@16: protected:
Chris@16:   F        fun_;
Chris@16:   const P1 p1_;
Chris@16:   const P2 p2_;
Chris@16:   const P3 p3_;
Chris@16:   const P4 p4_;
Chris@16: };
Chris@16: 
Chris@16: template<typename F,typename P1,typename P2,typename P3,typename P4>
Chris@16: inline scope_guard_impl4<F,P1,P2,P3,P4> make_guard(
Chris@16:   F fun,P1 p1,P2 p2,P3 p3,P4 p4)
Chris@16: {
Chris@16:   return scope_guard_impl4<F,P1,P2,P3,P4>(fun,p1,p2,p3,p4);
Chris@16: }
Chris@16: 
Chris@16: template<bool cond, typename F,typename P1,typename P2,typename P3,typename P4>
Chris@16: inline typename null_guard_return<cond,scope_guard_impl4<F,P1,P2,P3,P4> >::type 
Chris@16: make_guard_if_c(
Chris@16:   F fun,P1 p1,P2 p2,P3 p3,P4 p4)
Chris@16: {
Chris@16:   return typename null_guard_return<cond,scope_guard_impl4<F,P1,P2,P3,P4> >::type(fun,p1,p2,p3,p4);
Chris@16: }
Chris@16: 
Chris@16: template<typename C, typename F,typename P1,typename P2,typename P3,typename P4>
Chris@16: inline typename null_guard_return<C::value,scope_guard_impl4<F,P1,P2,P3,P4> >::type 
Chris@16: make_guard_if(
Chris@16:   F fun,P1 p1,P2 p2,P3 p3,P4 p4)
Chris@16: {
Chris@16:   return make_guard_if_c<C::value>(fun,p1,p2,p3,p4);
Chris@16: }
Chris@16: 
Chris@16: template<class Obj,typename MemFun>
Chris@16: class obj_scope_guard_impl0:public scope_guard_impl_base
Chris@16: {
Chris@16: public:
Chris@16:   obj_scope_guard_impl0(Obj& obj,MemFun mem_fun):obj_(obj),mem_fun_(mem_fun){}
Chris@16:   ~obj_scope_guard_impl0(){scope_guard_impl_base::safe_execute(*this);}
Chris@16:   void execute(){(obj_.*mem_fun_)();}
Chris@16: 
Chris@16: protected:
Chris@16:   Obj&   obj_;
Chris@16:   MemFun mem_fun_;
Chris@16: };
Chris@16: 
Chris@16: template<class Obj,typename MemFun>
Chris@16: inline obj_scope_guard_impl0<Obj,MemFun> make_obj_guard(Obj& obj,MemFun mem_fun)
Chris@16: {
Chris@16:   return obj_scope_guard_impl0<Obj,MemFun>(obj,mem_fun);
Chris@16: }
Chris@16: 
Chris@16: template<bool cond, class Obj,typename MemFun>
Chris@16: inline typename null_guard_return<cond,obj_scope_guard_impl0<Obj,MemFun> >::type 
Chris@16: make_obj_guard_if_c(Obj& obj,MemFun mem_fun)
Chris@16: {
Chris@16:   return typename null_guard_return<cond,obj_scope_guard_impl0<Obj,MemFun> >::type(obj,mem_fun);
Chris@16: }
Chris@16: 
Chris@16: template<typename C, class Obj,typename MemFun>
Chris@16: inline typename null_guard_return<C::value,obj_scope_guard_impl0<Obj,MemFun> >::type 
Chris@16: make_obj_guard_if(Obj& obj,MemFun mem_fun)
Chris@16: {
Chris@16:   return make_obj_guard_if_c<C::value>(obj,mem_fun);
Chris@16: }
Chris@16: 
Chris@16: template<class Obj,typename MemFun,typename P1>
Chris@16: class obj_scope_guard_impl1:public scope_guard_impl_base
Chris@16: {
Chris@16: public:
Chris@16:   obj_scope_guard_impl1(Obj& obj,MemFun mem_fun,P1 p1):
Chris@16:     obj_(obj),mem_fun_(mem_fun),p1_(p1){}
Chris@16:   ~obj_scope_guard_impl1(){scope_guard_impl_base::safe_execute(*this);}
Chris@16:   void execute(){(obj_.*mem_fun_)(p1_);}
Chris@16: 
Chris@16: protected:
Chris@16:   Obj&     obj_;
Chris@16:   MemFun   mem_fun_;
Chris@16:   const P1 p1_;
Chris@16: };
Chris@16: 
Chris@16: template<class Obj,typename MemFun,typename P1>
Chris@16: inline obj_scope_guard_impl1<Obj,MemFun,P1> make_obj_guard(
Chris@16:   Obj& obj,MemFun mem_fun,P1 p1)
Chris@16: {
Chris@16:   return obj_scope_guard_impl1<Obj,MemFun,P1>(obj,mem_fun,p1);
Chris@16: }
Chris@16: 
Chris@16: template<bool cond, class Obj,typename MemFun,typename P1>
Chris@16: inline typename null_guard_return<cond,obj_scope_guard_impl1<Obj,MemFun,P1> >::type 
Chris@16: make_obj_guard_if_c(  Obj& obj,MemFun mem_fun,P1 p1)
Chris@16: {
Chris@16:   return typename null_guard_return<cond,obj_scope_guard_impl1<Obj,MemFun,P1> >::type(obj,mem_fun,p1);
Chris@16: }
Chris@16: 
Chris@16: template<typename C, class Obj,typename MemFun,typename P1>
Chris@16: inline typename null_guard_return<C::value,obj_scope_guard_impl1<Obj,MemFun,P1> >::type 
Chris@16: make_obj_guard_if( Obj& obj,MemFun mem_fun,P1 p1)
Chris@16: {
Chris@16:   return make_obj_guard_if_c<C::value>(obj,mem_fun,p1);
Chris@16: }
Chris@16: 
Chris@16: template<class Obj,typename MemFun,typename P1,typename P2>
Chris@16: class obj_scope_guard_impl2:public scope_guard_impl_base
Chris@16: {
Chris@16: public:
Chris@16:   obj_scope_guard_impl2(Obj& obj,MemFun mem_fun,P1 p1,P2 p2):
Chris@16:     obj_(obj),mem_fun_(mem_fun),p1_(p1),p2_(p2)
Chris@16:   {}
Chris@16:   ~obj_scope_guard_impl2(){scope_guard_impl_base::safe_execute(*this);}
Chris@16:   void execute(){(obj_.*mem_fun_)(p1_,p2_);}
Chris@16: 
Chris@16: protected:
Chris@16:   Obj&     obj_;
Chris@16:   MemFun   mem_fun_;
Chris@16:   const P1 p1_;
Chris@16:   const P2 p2_;
Chris@16: };
Chris@16: 
Chris@16: template<class Obj,typename MemFun,typename P1,typename P2>
Chris@16: inline obj_scope_guard_impl2<Obj,MemFun,P1,P2>
Chris@16: make_obj_guard(Obj& obj,MemFun mem_fun,P1 p1,P2 p2)
Chris@16: {
Chris@16:   return obj_scope_guard_impl2<Obj,MemFun,P1,P2>(obj,mem_fun,p1,p2);
Chris@16: }
Chris@16: 
Chris@16: template<bool cond, class Obj,typename MemFun,typename P1,typename P2>
Chris@16: inline typename null_guard_return<cond,obj_scope_guard_impl2<Obj,MemFun,P1,P2> >::type
Chris@16: make_obj_guard_if_c(Obj& obj,MemFun mem_fun,P1 p1,P2 p2)
Chris@16: {
Chris@16:   return typename null_guard_return<cond,obj_scope_guard_impl2<Obj,MemFun,P1,P2> >::type(obj,mem_fun,p1,p2);
Chris@16: }
Chris@16: 
Chris@16: template<typename C, class Obj,typename MemFun,typename P1,typename P2>
Chris@16: inline typename null_guard_return<C::value,obj_scope_guard_impl2<Obj,MemFun,P1,P2> >::type
Chris@16: make_obj_guard_if(Obj& obj,MemFun mem_fun,P1 p1,P2 p2)
Chris@16: {
Chris@16:   return make_obj_guard_if_c<C::value>(obj,mem_fun,p1,p2);
Chris@16: }
Chris@16: 
Chris@16: template<class Obj,typename MemFun,typename P1,typename P2,typename P3>
Chris@16: class obj_scope_guard_impl3:public scope_guard_impl_base
Chris@16: {
Chris@16: public:
Chris@16:   obj_scope_guard_impl3(Obj& obj,MemFun mem_fun,P1 p1,P2 p2,P3 p3):
Chris@16:     obj_(obj),mem_fun_(mem_fun),p1_(p1),p2_(p2),p3_(p3)
Chris@16:   {}
Chris@16:   ~obj_scope_guard_impl3(){scope_guard_impl_base::safe_execute(*this);}
Chris@16:   void execute(){(obj_.*mem_fun_)(p1_,p2_,p3_);}
Chris@16: 
Chris@16: protected:
Chris@16:   Obj&     obj_;
Chris@16:   MemFun   mem_fun_;
Chris@16:   const P1 p1_;
Chris@16:   const P2 p2_;
Chris@16:   const P3 p3_;
Chris@16: };
Chris@16: 
Chris@16: template<class Obj,typename MemFun,typename P1,typename P2,typename P3>
Chris@16: inline obj_scope_guard_impl3<Obj,MemFun,P1,P2,P3>
Chris@16: make_obj_guard(Obj& obj,MemFun mem_fun,P1 p1,P2 p2,P3 p3)
Chris@16: {
Chris@16:   return obj_scope_guard_impl3<Obj,MemFun,P1,P2,P3>(obj,mem_fun,p1,p2,p3);
Chris@16: }
Chris@16: 
Chris@16: template<bool cond, class Obj,typename MemFun,typename P1,typename P2,typename P3>
Chris@16: inline typename null_guard_return<cond,obj_scope_guard_impl3<Obj,MemFun,P1,P2,P3> >::type
Chris@16: make_obj_guard_if_c(Obj& obj,MemFun mem_fun,P1 p1,P2 p2,P3 p3)
Chris@16: {
Chris@16:   return typename null_guard_return<cond,obj_scope_guard_impl3<Obj,MemFun,P1,P2,P3> >::type(obj,mem_fun,p1,p2,p3);
Chris@16: }
Chris@16: 
Chris@16: template<typename C, class Obj,typename MemFun,typename P1,typename P2,typename P3>
Chris@16: inline typename null_guard_return<C::value,obj_scope_guard_impl3<Obj,MemFun,P1,P2,P3> >::type
Chris@16: make_obj_guard_if(Obj& obj,MemFun mem_fun,P1 p1,P2 p2,P3 p3)
Chris@16: {
Chris@16:   return make_obj_guard_if_c<C::value>(obj,mem_fun,p1,p2,p3);
Chris@16: }
Chris@16: 
Chris@16: } /* namespace multi_index::detail */
Chris@16: 
Chris@16: } /* namespace multi_index */
Chris@16: 
Chris@16: } /* namespace boost */
Chris@16: 
Chris@16: #endif