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| 1 | +#ifndef __ADDR_PRI_H__ |
| 2 | +#define __ADDR_PRI_H__ |
| 3 | + |
| 4 | + |
| 5 | +#include <utility> |
| 6 | +#include <type_traits> |
| 7 | + |
| 8 | + |
| 9 | + |
| 10 | +//base on C++11 |
| 11 | + |
| 12 | +/********************************************************** |
| 13 | + access private function |
| 14 | +**********************************************************/ |
| 15 | + |
| 16 | + |
| 17 | +namespace std { |
| 18 | + template <bool B, class T = void> |
| 19 | + using enable_if_t = typename enable_if<B, T>::type; |
| 20 | + template <class T> |
| 21 | + using remove_reference_t = typename remove_reference<T>::type; |
| 22 | +} // std |
| 23 | + |
| 24 | +// Unnamed namespace is used to avoid duplicate symbols if the macros are used |
| 25 | +namespace { |
| 26 | + namespace private_access_detail { |
| 27 | + |
| 28 | + // @tparam TagType, used to declare different "get" funciton overloads for |
| 29 | + // different members/statics |
| 30 | + template <typename PtrType, PtrType PtrValue, typename TagType> |
| 31 | + struct private_access { |
| 32 | + // Normal lookup cannot find in-class defined (inline) friend functions. |
| 33 | + friend PtrType get(TagType) { return PtrValue; } |
| 34 | + }; |
| 35 | + |
| 36 | + } // namespace private_access_detail |
| 37 | +} // namespace |
| 38 | + |
| 39 | +// Used macro naming conventions: |
| 40 | +// The "namespace" of this macro library is PRIVATE_ACCESS, i.e. all |
| 41 | +// macro here has this prefix. |
| 42 | +// All implementation macro, which are not meant to be used directly have the |
| 43 | +// PRIVATE_ACCESS_DETAIL prefix. |
| 44 | +// Some macros have the ABCD_IMPL form, which means they contain the |
| 45 | +// implementation details for the specific ABCD macro. |
| 46 | + |
| 47 | +#define PRIVATE_ACCESS_DETAIL_CONCATENATE_IMPL(x, y) x##y |
| 48 | +#define PRIVATE_ACCESS_DETAIL_CONCATENATE(x, y) \ |
| 49 | + PRIVATE_ACCESS_DETAIL_CONCATENATE_IMPL(x, y) |
| 50 | + |
| 51 | +// @param PtrTypeKind E.g if we have "class A", then it can be "A::*" in case of |
| 52 | +// members, or it can be "*" in case of statics. |
| 53 | +#define PRIVATE_ACCESS_DETAIL_ACCESS_PRIVATE(Tag, Class, Type, Name, \ |
| 54 | + PtrTypeKind) \ |
| 55 | + namespace { \ |
| 56 | + namespace private_access_detail { \ |
| 57 | + /* Tag type, used to declare different get funcitons for different \ |
| 58 | + * members \ |
| 59 | + */ \ |
| 60 | + struct Tag {}; \ |
| 61 | + /* Explicit instantiation */ \ |
| 62 | + template struct private_access<decltype(&Class::Name), &Class::Name, \ |
| 63 | + Tag>; \ |
| 64 | + /* We can build the PtrType only with two aliases */ \ |
| 65 | + /* E.g. using PtrType = int(int) *; would be illformed */ \ |
| 66 | + using PRIVATE_ACCESS_DETAIL_CONCATENATE(Alias_, Tag) = Type; \ |
| 67 | + using PRIVATE_ACCESS_DETAIL_CONCATENATE(PtrType_, Tag) = \ |
| 68 | + PRIVATE_ACCESS_DETAIL_CONCATENATE(Alias_, Tag) PtrTypeKind; \ |
| 69 | + /* Declare the friend function, now it is visible in namespace scope. \ |
| 70 | + * Note, \ |
| 71 | + * we could declare it inside the Tag type too, in that case ADL would \ |
| 72 | + * find \ |
| 73 | + * the declaration. By choosing to declare it here, the Tag type remains \ |
| 74 | + * a \ |
| 75 | + * simple tag type, it has no other responsibilities. */ \ |
| 76 | + PRIVATE_ACCESS_DETAIL_CONCATENATE(PtrType_, Tag) get(Tag); \ |
| 77 | + } \ |
| 78 | + } |
| 79 | + |
| 80 | +#define PRIVATE_ACCESS_DETAIL_ACCESS_PRIVATE_FIELD(Tag, Class, Type, Name) \ |
| 81 | + PRIVATE_ACCESS_DETAIL_ACCESS_PRIVATE(Tag, Class, Type, Name, Class::*) \ |
| 82 | + namespace { \ |
| 83 | + namespace access_private_field { \ |
| 84 | + Type &Class##Name(Class &&t) { return t.*get(private_access_detail::Tag{}); } \ |
| 85 | + Type &Class##Name(Class &t) { return t.*get(private_access_detail::Tag{}); } \ |
| 86 | + /* The following usings are here to avoid duplicate const qualifier \ |
| 87 | + * warnings \ |
| 88 | + */ \ |
| 89 | + using PRIVATE_ACCESS_DETAIL_CONCATENATE(X, Tag) = Type; \ |
| 90 | + using PRIVATE_ACCESS_DETAIL_CONCATENATE(Y, Tag) = \ |
| 91 | + const PRIVATE_ACCESS_DETAIL_CONCATENATE(X, Tag); \ |
| 92 | + PRIVATE_ACCESS_DETAIL_CONCATENATE(Y, Tag) & Class##Name(const Class &t) {\ |
| 93 | + return t.*get(private_access_detail::Tag{}); \ |
| 94 | + } \ |
| 95 | + } \ |
| 96 | + } |
| 97 | + |
| 98 | +#define PRIVATE_ACCESS_DETAIL_ACCESS_PRIVATE_FUN(Tag, Class, Type, Name) \ |
| 99 | + PRIVATE_ACCESS_DETAIL_ACCESS_PRIVATE(Tag, Class, Type, Name, Class::*) \ |
| 100 | + namespace { \ |
| 101 | + namespace call_private_fun { \ |
| 102 | + /* We do perfect forwarding, but we want to restrict the overload set \ |
| 103 | + * only for objects which have the type Class. */ \ |
| 104 | + template <typename Obj, \ |
| 105 | + std::enable_if_t<std::is_same<std::remove_reference_t<Obj>, \ |
| 106 | + Class>::value> * = nullptr, \ |
| 107 | + typename... Args> \ |
| 108 | + auto Class##Name(Obj &&o, Args &&... args) -> decltype( \ |
| 109 | + (std::forward<Obj>(o).* \ |
| 110 | + get(private_access_detail::Tag{}))(std::forward<Args>(args)...)) { \ |
| 111 | + return (std::forward<Obj>(o).*get(private_access_detail::Tag{}))( \ |
| 112 | + std::forward<Args>(args)...); \ |
| 113 | + } \ |
| 114 | + } \ |
| 115 | + namespace get_private_fun { \ |
| 116 | + auto Class##Name() -> decltype( \ |
| 117 | + get(private_access_detail::Tag{})) { \ |
| 118 | + return (get(private_access_detail::Tag{})); \ |
| 119 | + } \ |
| 120 | + } \ |
| 121 | + } |
| 122 | + |
| 123 | +#define PRIVATE_ACCESS_DETAIL_ACCESS_PRIVATE_STATIC_FIELD(Tag, Class, Type, \ |
| 124 | + Name) \ |
| 125 | + PRIVATE_ACCESS_DETAIL_ACCESS_PRIVATE(Tag, Class, Type, Name, *) \ |
| 126 | + namespace { \ |
| 127 | + namespace access_private_static_field { \ |
| 128 | + namespace Class { \ |
| 129 | + Type &Class##Name() { return *get(private_access_detail::Tag{}); } \ |
| 130 | + } \ |
| 131 | + } \ |
| 132 | + } |
| 133 | + |
| 134 | +#define PRIVATE_ACCESS_DETAIL_ACCESS_PRIVATE_STATIC_FUN(Tag, Class, Type, \ |
| 135 | + Name) \ |
| 136 | + PRIVATE_ACCESS_DETAIL_ACCESS_PRIVATE(Tag, Class, Type, Name, *) \ |
| 137 | + namespace { \ |
| 138 | + namespace call_private_static_fun { \ |
| 139 | + namespace Class { \ |
| 140 | + template <typename... Args> \ |
| 141 | + auto Class##Name(Args &&... args) -> decltype( \ |
| 142 | + get(private_access_detail::Tag{})(std::forward<Args>(args)...)) { \ |
| 143 | + return get(private_access_detail::Tag{})( \ |
| 144 | + std::forward<Args>(args)...); \ |
| 145 | + } \ |
| 146 | + } \ |
| 147 | + } \ |
| 148 | + namespace get_private_static_fun { \ |
| 149 | + namespace Class { \ |
| 150 | + auto Class##Name() -> decltype(get(private_access_detail::Tag{})) { \ |
| 151 | + return get(private_access_detail::Tag{}); \ |
| 152 | + } \ |
| 153 | + } \ |
| 154 | + } \ |
| 155 | + } |
| 156 | + |
| 157 | +#define PRIVATE_ACCESS_DETAIL_UNIQUE_TAG \ |
| 158 | + PRIVATE_ACCESS_DETAIL_CONCATENATE(PrivateAccessTag, __COUNTER__) |
| 159 | + |
| 160 | +#define ACCESS_PRIVATE_FIELD(Class, Type, Name) \ |
| 161 | + PRIVATE_ACCESS_DETAIL_ACCESS_PRIVATE_FIELD(PRIVATE_ACCESS_DETAIL_UNIQUE_TAG, \ |
| 162 | + Class, Type, Name) |
| 163 | + |
| 164 | +#define ACCESS_PRIVATE_FUN(Class, Type, Name) \ |
| 165 | + PRIVATE_ACCESS_DETAIL_ACCESS_PRIVATE_FUN(PRIVATE_ACCESS_DETAIL_UNIQUE_TAG, \ |
| 166 | + Class, Type, Name) |
| 167 | + |
| 168 | +#define ACCESS_PRIVATE_STATIC_FIELD(Class, Type, Name) \ |
| 169 | + Type Class::Name; \ |
| 170 | + PRIVATE_ACCESS_DETAIL_ACCESS_PRIVATE_STATIC_FIELD( \ |
| 171 | + PRIVATE_ACCESS_DETAIL_UNIQUE_TAG, Class, Type, Name) |
| 172 | + |
| 173 | +#define ACCESS_PRIVATE_STATIC_FUN(Class, Type, Name) \ |
| 174 | + PRIVATE_ACCESS_DETAIL_ACCESS_PRIVATE_STATIC_FUN( \ |
| 175 | + PRIVATE_ACCESS_DETAIL_UNIQUE_TAG, Class, Type, Name) |
| 176 | + |
| 177 | +#endif |
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