1 /* Copyright 2003-2013 Joaquin M Lopez Munoz.
2 * 2019 Mike Dev <mike.dev@gmx.de>
3 * Distributed under the Boost Software License, Version 1.0.
4 * (See accompanying file LICENSE_1_0.txt or copy at
5 * https://www.boost.org/LICENSE_1_0.txt)
6 *
7 * NOTE: internalized from Boost.MultiIndex
8 *
9 */
10
11
12 #ifndef BOOST_SIGNALS2_DETAIL_SCOPE_GUARD_HPP
13 #define BOOST_SIGNALS2_DETAIL_SCOPE_GUARD_HPP
14
15 #if defined(_MSC_VER)
16 #pragma once
17 #endif
18
19 #include <boost/core/no_exceptions_support.hpp>
20
21 namespace boost{
22
23 namespace signals2{
24
25 namespace detail{
26
27 /* This is a merely reformated version of
28 * ScopeGuard.h as defined in:
29 * Alexandrescu, A., Marginean, P.:"Generic<Programming>: Change the Way You
30 * Write Exception-Safe Code - Forever", C/C++ Users Jornal, Dec 2000,
31 * http://www.drdobbs.com/184403758
32 * with the following modifications:
33 * - General pretty formatting (pretty to my taste at least.)
34 * - Naming style changed to standard C++ library requirements.
35 * - Removed RefHolder and ByRef, whose functionality is provided
36 * already by Boost.Ref.
37 * - Removed static make_guard's and make_obj_guard's, so that the code
38 * will work even if BOOST_NO_MEMBER_TEMPLATES is defined. This forces
39 * us to move some private ctors to public, though.
40 *
41 * NB: CodeWarrior Pro 8 seems to have problems looking up safe_execute
42 * without an explicit qualification.
43 *
44 * TODO: Consider replacing with Boost.ScopeExit
45 *
46 */
47
48 class scope_guard_impl_base
49 {
50 public:
scope_guard_impl_base()51 scope_guard_impl_base():dismissed_(false){}
dismiss() const52 void dismiss()const{dismissed_=true;}
53
54 protected:
~scope_guard_impl_base()55 ~scope_guard_impl_base(){}
56
scope_guard_impl_base(const scope_guard_impl_base & other)57 scope_guard_impl_base(const scope_guard_impl_base& other):
58 dismissed_(other.dismissed_)
59 {
60 other.dismiss();
61 }
62
63 template<typename J>
safe_execute(J & j)64 static void safe_execute(J& j){
65 BOOST_TRY{
66 if(!j.dismissed_)j.execute();
67 }
68 BOOST_CATCH(...){}
69 BOOST_CATCH_END
70 }
71
72 mutable bool dismissed_;
73
74 private:
75 scope_guard_impl_base& operator=(const scope_guard_impl_base&);
76 };
77
78 typedef const scope_guard_impl_base& scope_guard;
79
80 template<class Obj,typename MemFun,typename P1,typename P2>
81 class obj_scope_guard_impl2:public scope_guard_impl_base
82 {
83 public:
obj_scope_guard_impl2(Obj & obj,MemFun mem_fun,P1 p1,P2 p2)84 obj_scope_guard_impl2(Obj& obj,MemFun mem_fun,P1 p1,P2 p2):
85 obj_(obj),mem_fun_(mem_fun),p1_(p1),p2_(p2)
86 {}
~obj_scope_guard_impl2()87 ~obj_scope_guard_impl2(){scope_guard_impl_base::safe_execute(*this);}
execute()88 void execute(){(obj_.*mem_fun_)(p1_,p2_);}
89
90 protected:
91 Obj& obj_;
92 MemFun mem_fun_;
93 const P1 p1_;
94 const P2 p2_;
95 };
96
97 template<class Obj,typename MemFun,typename P1,typename P2>
98 inline obj_scope_guard_impl2<Obj,MemFun,P1,P2>
make_obj_guard(Obj & obj,MemFun mem_fun,P1 p1,P2 p2)99 make_obj_guard(Obj& obj,MemFun mem_fun,P1 p1,P2 p2)
100 {
101 return obj_scope_guard_impl2<Obj,MemFun,P1,P2>(obj,mem_fun,p1,p2);
102 }
103
104 } /* namespace signals2::detail */
105
106 } /* namespace signals2 */
107
108 } /* namespace boost */
109
110 #endif
111