williamr@2: /* Copyright 2003-2005 Joaquín M López Muñoz.
williamr@2:  * Distributed under the Boost Software License, Version 1.0.
williamr@2:  * (See accompanying file LICENSE_1_0.txt or copy at
williamr@2:  * http://www.boost.org/LICENSE_1_0.txt)
williamr@2:  *
williamr@2:  * See http://www.boost.org/libs/multi_index for library home page.
williamr@2:  */
williamr@2: 
williamr@2: #ifndef BOOST_MULTI_INDEX_DETAIL_SCOPE_GUARD_HPP
williamr@2: #define BOOST_MULTI_INDEX_DETAIL_SCOPE_GUARD_HPP
williamr@2: 
williamr@2: #if defined(_MSC_VER)&&(_MSC_VER>=1200)
williamr@2: #pragma once
williamr@2: #endif
williamr@2: 
williamr@2: namespace boost{
williamr@2: 
williamr@2: namespace multi_index{
williamr@2: 
williamr@2: namespace detail{
williamr@2: 
williamr@2: /* Until some official version of the ScopeGuard idiom makes it into Boost,
williamr@2:  * we locally define our own. This is a merely reformated version of
williamr@2:  * ScopeGuard.h as defined in:
williamr@2:  *   Alexandrescu, A., Marginean, P.:"Generic<Programming>: Change the Way You
williamr@2:  *     Write Exception-Safe Code - Forever", C/C++ Users Jornal, Dec 2000,
williamr@2:  *     http://www.cuj.com/documents/s=8000/cujcexp1812alexandr/
williamr@2:  * with the following modifications:
williamr@2:  *   - General pretty formatting (pretty to my taste at least.)
williamr@2:  *   - Naming style changed to standard C++ library requirements.
williamr@2:  *   - safe_execute does not feature a try-catch protection, so we can
williamr@2:  *     use this even if BOOST_NO_EXCEPTIONS is defined.
williamr@2:  *   - Added scope_guard_impl4 and obj_scope_guard_impl3, (Boost.MultiIndex
williamr@2:  *     needs them). A better design would provide guards for many more
williamr@2:  *     arguments through the Boost Preprocessor Library.
williamr@2:  *   - Added scope_guard_impl_base::touch (see below.)
williamr@2:  *   - Removed RefHolder and ByRef, whose functionality is provided
williamr@2:  *     already by Boost.Ref.
williamr@2:  *   - Removed static make_guard's and make_obj_guard's, so that the code
williamr@2:  *     will work even if BOOST_NO_MEMBER_TEMPLATES is defined. This forces
williamr@2:  *     us to move some private ctors to public, though.
williamr@2:  *
williamr@2:  * NB: CodeWarrior Pro 8 seems to have problems looking up safe_execute
williamr@2:  * without an explicit qualification.
williamr@2:  */
williamr@2: 
williamr@2: class scope_guard_impl_base
williamr@2: {
williamr@2: public:
williamr@2:   scope_guard_impl_base():dismissed_(false){}
williamr@2:   void dismiss()const{dismissed_=true;}
williamr@2: 
williamr@2:   /* This helps prevent some "unused variable" warnings under, for instance,
williamr@2:    * GCC 3.2.
williamr@2:    */
williamr@2:   void touch()const{}
williamr@2: 
williamr@2: protected:
williamr@2:   ~scope_guard_impl_base(){}
williamr@2: 
williamr@2:   scope_guard_impl_base(const scope_guard_impl_base& other):
williamr@2:     dismissed_(other.dismissed_)
williamr@2:   {
williamr@2:     other.dismiss();
williamr@2:   }
williamr@2: 
williamr@2:   template<typename J>
williamr@2:   static void safe_execute(J& j){if(!j.dismissed_)j.execute();}
williamr@2:   
williamr@2:   mutable bool dismissed_;
williamr@2: 
williamr@2: private:
williamr@2:   scope_guard_impl_base& operator=(const scope_guard_impl_base&);
williamr@2: };
williamr@2: 
williamr@2: typedef const scope_guard_impl_base& scope_guard;
williamr@2: 
williamr@2: template<typename F>
williamr@2: class scope_guard_impl0:public scope_guard_impl_base
williamr@2: {
williamr@2: public:
williamr@2:   scope_guard_impl0(F fun):fun_(fun){}
williamr@2:   ~scope_guard_impl0(){scope_guard_impl_base::safe_execute(*this);}
williamr@2:   void execute(){fun_();}
williamr@2: 
williamr@2: protected:
williamr@2: 
williamr@2:   F fun_;
williamr@2: };
williamr@2: 
williamr@2: template<typename F> 
williamr@2: inline scope_guard_impl0<F> make_guard(F fun)
williamr@2: {
williamr@2:   return scope_guard_impl0<F>(fun);
williamr@2: }
williamr@2: 
williamr@2: template<typename F,typename P1>
williamr@2: class scope_guard_impl1:public scope_guard_impl_base
williamr@2: {
williamr@2: public:
williamr@2:   scope_guard_impl1(F fun,P1 p1):fun_(fun),p1_(p1){}
williamr@2:   ~scope_guard_impl1(){scope_guard_impl_base::safe_execute(*this);}
williamr@2:   void execute(){fun_(p1_);}
williamr@2: 
williamr@2: protected:
williamr@2:   F        fun_;
williamr@2:   const P1 p1_;
williamr@2: };
williamr@2: 
williamr@2: template<typename F,typename P1> 
williamr@2: inline scope_guard_impl1<F,P1> make_guard(F fun,P1 p1)
williamr@2: {
williamr@2:   return scope_guard_impl1<F,P1>(fun,p1);
williamr@2: }
williamr@2: 
williamr@2: template<typename F,typename P1,typename P2>
williamr@2: class scope_guard_impl2:public scope_guard_impl_base
williamr@2: {
williamr@2: public:
williamr@2:   scope_guard_impl2(F fun,P1 p1,P2 p2):fun_(fun),p1_(p1),p2_(p2){}
williamr@2:   ~scope_guard_impl2(){scope_guard_impl_base::safe_execute(*this);}
williamr@2:   void execute(){fun_(p1_,p2_);}
williamr@2: 
williamr@2: protected:
williamr@2:   F        fun_;
williamr@2:   const P1 p1_;
williamr@2:   const P2 p2_;
williamr@2: };
williamr@2: 
williamr@2: template<typename F,typename P1,typename P2>
williamr@2: inline scope_guard_impl2<F,P1,P2> make_guard(F fun,P1 p1,P2 p2)
williamr@2: {
williamr@2:   return scope_guard_impl2<F,P1,P2>(fun,p1,p2);
williamr@2: }
williamr@2: 
williamr@2: template<typename F,typename P1,typename P2,typename P3>
williamr@2: class scope_guard_impl3:public scope_guard_impl_base
williamr@2: {
williamr@2: public:
williamr@2:   scope_guard_impl3(F fun,P1 p1,P2 p2,P3 p3):fun_(fun),p1_(p1),p2_(p2),p3_(p3){}
williamr@2:   ~scope_guard_impl3(){scope_guard_impl_base::safe_execute(*this);}
williamr@2:   void execute(){fun_(p1_,p2_,p3_);}
williamr@2: 
williamr@2: protected:
williamr@2:   F        fun_;
williamr@2:   const P1 p1_;
williamr@2:   const P2 p2_;
williamr@2:   const P3 p3_;
williamr@2: };
williamr@2: 
williamr@2: template<typename F,typename P1,typename P2,typename P3>
williamr@2: inline scope_guard_impl3<F,P1,P2,P3> make_guard(F fun,P1 p1,P2 p2,P3 p3)
williamr@2: {
williamr@2:   return scope_guard_impl3<F,P1,P2,P3>(fun,p1,p2,p3);
williamr@2: }
williamr@2: 
williamr@2: template<typename F,typename P1,typename P2,typename P3,typename P4>
williamr@2: class scope_guard_impl4:public scope_guard_impl_base
williamr@2: {
williamr@2: public:
williamr@2:   scope_guard_impl4(F fun,P1 p1,P2 p2,P3 p3,P4 p4):
williamr@2:     fun_(fun),p1_(p1),p2_(p2),p3_(p3),p4_(p4){}
williamr@2:   ~scope_guard_impl4(){scope_guard_impl_base::safe_execute(*this);}
williamr@2:   void execute(){fun_(p1_,p2_,p3_,p4_);}
williamr@2: 
williamr@2: protected:
williamr@2:   F        fun_;
williamr@2:   const P1 p1_;
williamr@2:   const P2 p2_;
williamr@2:   const P3 p3_;
williamr@2:   const P4 p4_;
williamr@2: };
williamr@2: 
williamr@2: template<typename F,typename P1,typename P2,typename P3,typename P4>
williamr@2: inline scope_guard_impl4<F,P1,P2,P3,P4> make_guard(
williamr@2:   F fun,P1 p1,P2 p2,P3 p3,P4 p4)
williamr@2: {
williamr@2:   return scope_guard_impl4<F,P1,P2,P3,P4>(fun,p1,p2,p3,p4);
williamr@2: }
williamr@2: 
williamr@2: template<class Obj,typename MemFun>
williamr@2: class obj_scope_guard_impl0:public scope_guard_impl_base
williamr@2: {
williamr@2: public:
williamr@2:   obj_scope_guard_impl0(Obj& obj,MemFun mem_fun):obj_(obj),mem_fun_(mem_fun){}
williamr@2:   ~obj_scope_guard_impl0(){scope_guard_impl_base::safe_execute(*this);}
williamr@2:   void execute(){(obj_.*mem_fun_)();}
williamr@2: 
williamr@2: protected:
williamr@2:   Obj&   obj_;
williamr@2:   MemFun mem_fun_;
williamr@2: };
williamr@2: 
williamr@2: template<class Obj,typename MemFun>
williamr@2: inline obj_scope_guard_impl0<Obj,MemFun> make_obj_guard(Obj& obj,MemFun mem_fun)
williamr@2: {
williamr@2:   return obj_scope_guard_impl0<Obj,MemFun>(obj,mem_fun);
williamr@2: }
williamr@2: 
williamr@2: template<class Obj,typename MemFun,typename P1>
williamr@2: class obj_scope_guard_impl1:public scope_guard_impl_base
williamr@2: {
williamr@2: public:
williamr@2:   obj_scope_guard_impl1(Obj& obj,MemFun mem_fun,P1 p1):
williamr@2:     obj_(obj),mem_fun_(mem_fun),p1_(p1){}
williamr@2:   ~obj_scope_guard_impl1(){scope_guard_impl_base::safe_execute(*this);}
williamr@2:   void execute(){(obj_.*mem_fun_)(p1_);}
williamr@2: 
williamr@2: protected:
williamr@2:   Obj&     obj_;
williamr@2:   MemFun   mem_fun_;
williamr@2:   const P1 p1_;
williamr@2: };
williamr@2: 
williamr@2: template<class Obj,typename MemFun,typename P1>
williamr@2: inline obj_scope_guard_impl1<Obj,MemFun,P1> make_obj_guard(
williamr@2:   Obj& obj,MemFun mem_fun,P1 p1)
williamr@2: {
williamr@2:   return obj_scope_guard_impl1<Obj,MemFun,P1>(obj,mem_fun,p1);
williamr@2: }
williamr@2: 
williamr@2: template<class Obj,typename MemFun,typename P1,typename P2>
williamr@2: class obj_scope_guard_impl2:public scope_guard_impl_base
williamr@2: {
williamr@2: public:
williamr@2:   obj_scope_guard_impl2(Obj& obj,MemFun mem_fun,P1 p1,P2 p2):
williamr@2:     obj_(obj),mem_fun_(mem_fun),p1_(p1),p2_(p2)
williamr@2:   {}
williamr@2:   ~obj_scope_guard_impl2(){scope_guard_impl_base::safe_execute(*this);}
williamr@2:   void execute(){(obj_.*mem_fun_)(p1_,p2_);}
williamr@2: 
williamr@2: protected:
williamr@2:   Obj&     obj_;
williamr@2:   MemFun   mem_fun_;
williamr@2:   const P1 p1_;
williamr@2:   const P2 p2_;
williamr@2: };
williamr@2: 
williamr@2: template<class Obj,typename MemFun,typename P1,typename P2>
williamr@2: inline obj_scope_guard_impl2<Obj,MemFun,P1,P2>
williamr@2: make_obj_guard(Obj& obj,MemFun mem_fun,P1 p1,P2 p2)
williamr@2: {
williamr@2:   return obj_scope_guard_impl2<Obj,MemFun,P1,P2>(obj,mem_fun,p1,p2);
williamr@2: }
williamr@2: 
williamr@2: template<class Obj,typename MemFun,typename P1,typename P2,typename P3>
williamr@2: class obj_scope_guard_impl3:public scope_guard_impl_base
williamr@2: {
williamr@2: public:
williamr@2:   obj_scope_guard_impl3(Obj& obj,MemFun mem_fun,P1 p1,P2 p2,P3 p3):
williamr@2:     obj_(obj),mem_fun_(mem_fun),p1_(p1),p2_(p2),p3_(p3)
williamr@2:   {}
williamr@2:   ~obj_scope_guard_impl3(){scope_guard_impl_base::safe_execute(*this);}
williamr@2:   void execute(){(obj_.*mem_fun_)(p1_,p2_,p3_);}
williamr@2: 
williamr@2: protected:
williamr@2:   Obj&     obj_;
williamr@2:   MemFun   mem_fun_;
williamr@2:   const P1 p1_;
williamr@2:   const P2 p2_;
williamr@2:   const P3 p3_;
williamr@2: };
williamr@2: 
williamr@2: template<class Obj,typename MemFun,typename P1,typename P2,typename P3>
williamr@2: inline obj_scope_guard_impl3<Obj,MemFun,P1,P2,P3>
williamr@2: make_obj_guard(Obj& obj,MemFun mem_fun,P1 p1,P2 p2,P3 p3)
williamr@2: {
williamr@2:   return obj_scope_guard_impl3<Obj,MemFun,P1,P2,P3>(obj,mem_fun,p1,p2,p3);
williamr@2: }
williamr@2: 
williamr@2: } /* namespace multi_index::detail */
williamr@2: 
williamr@2: } /* namespace multi_index */
williamr@2: 
williamr@2: } /* namespace boost */
williamr@2: 
williamr@2: #endif