1 // Protocol Buffers - Google's data interchange format
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30 
31 #ifndef GOOGLE_PROTOBUF_MAP_ENTRY_H__
32 #define GOOGLE_PROTOBUF_MAP_ENTRY_H__
33 
34 #include <google/protobuf/generated_message_reflection.h>
35 #include <google/protobuf/map_entry_lite.h>
36 #include <google/protobuf/map_type_handler.h>
37 #include <google/protobuf/port.h>
38 #include <google/protobuf/reflection_ops.h>
39 #include <google/protobuf/unknown_field_set.h>
40 #include <google/protobuf/wire_format_lite.h>
41 
42 #include <google/protobuf/port_def.inc>
43 
44 #ifdef SWIG
45 #error "You cannot SWIG proto headers"
46 #endif
47 
48 namespace google {
49 namespace protobuf {
50 class Arena;
51 namespace internal {
52 template <typename Derived, typename Key, typename Value,
53           WireFormatLite::FieldType kKeyFieldType,
54           WireFormatLite::FieldType kValueFieldType>
55 class MapField;
56 }
57 }  // namespace protobuf
58 }  // namespace google
59 
60 namespace google {
61 namespace protobuf {
62 namespace internal {
63 
64 // MapEntry is the returned google::protobuf::Message when calling AddMessage of
65 // google::protobuf::Reflection. In order to let it work with generated message
66 // reflection, its in-memory type is the same as generated message with the same
67 // fields. However, in order to decide the in-memory type of key/value, we need
68 // to know both their cpp type in generated api and proto type. In
69 // implementation, all in-memory types have related wire format functions to
70 // support except ArenaStringPtr. Therefore, we need to define another type with
71 // supporting wire format functions. Since this type is only used as return type
72 // of MapEntry accessors, it's named MapEntry accessor type.
73 //
74 // cpp type:               the type visible to users in public API.
75 // proto type:             WireFormatLite::FieldType of the field.
76 // in-memory type:         type of the data member used to stored this field.
77 // MapEntry accessor type: type used in MapEntry getters/mutators to access the
78 //                         field.
79 //
80 // cpp type | proto type  | in-memory type | MapEntry accessor type
81 // int32      TYPE_INT32    int32            int32
82 // int32      TYPE_FIXED32  int32            int32
83 // string     TYPE_STRING   ArenaStringPtr   string
84 // FooEnum    TYPE_ENUM     int              int
85 // FooMessage TYPE_MESSAGE  FooMessage*      FooMessage
86 //
87 // The in-memory types of primitive types can be inferred from its proto type,
88 // while we need to explicitly specify the cpp type if proto type is
89 // TYPE_MESSAGE to infer the in-memory type.
90 template <typename Derived, typename Key, typename Value,
91           WireFormatLite::FieldType kKeyFieldType,
92           WireFormatLite::FieldType kValueFieldType>
93 class MapEntry : public MapEntryImpl<Derived, Message, Key, Value,
94                                      kKeyFieldType, kValueFieldType> {
95  public:
MapEntry()96   constexpr MapEntry() : _internal_metadata_() {}
MapEntry(Arena * arena)97   explicit MapEntry(Arena* arena)
98       : MapEntryImpl<Derived, Message, Key, Value, kKeyFieldType,
99                      kValueFieldType>(arena),
100         _internal_metadata_(arena) {}
~MapEntry()101   ~MapEntry() {
102     Message::_internal_metadata_.template Delete<UnknownFieldSet>();
103     _internal_metadata_.Delete<UnknownFieldSet>();
104   }
105   typedef void InternalArenaConstructable_;
106   typedef void DestructorSkippable_;
107 
108   typedef typename MapEntryImpl<Derived, Message, Key, Value, kKeyFieldType,
109                                 kValueFieldType>::KeyTypeHandler KeyTypeHandler;
110   typedef
111       typename MapEntryImpl<Derived, Message, Key, Value, kKeyFieldType,
112                             kValueFieldType>::ValueTypeHandler ValueTypeHandler;
SpaceUsedLong()113   size_t SpaceUsedLong() const override {
114     size_t size = sizeof(Derived);
115     size += KeyTypeHandler::SpaceUsedInMapEntryLong(this->key_);
116     size += ValueTypeHandler::SpaceUsedInMapEntryLong(this->value_);
117     return size;
118   }
119 
120   InternalMetadata _internal_metadata_;
121 
122  private:
123   friend class ::PROTOBUF_NAMESPACE_ID::Arena;
124   template <typename C, typename K, typename V,
125             WireFormatLite::FieldType k_wire_type, WireFormatLite::FieldType>
126   friend class internal::MapField;
127 
128   GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(MapEntry);
129 };
130 
131 // Specialization for the full runtime
132 template <typename Derived, typename Key, typename Value,
133           WireFormatLite::FieldType kKeyFieldType,
134           WireFormatLite::FieldType kValueFieldType>
135 struct MapEntryHelper<
136     MapEntry<Derived, Key, Value, kKeyFieldType, kValueFieldType> >
137     : MapEntryHelper<
138           MapEntryLite<Derived, Key, Value, kKeyFieldType, kValueFieldType> > {
139   explicit MapEntryHelper(const MapPair<Key, Value>& map_pair)
140       : MapEntryHelper<
141             MapEntryLite<Derived, Key, Value, kKeyFieldType, kValueFieldType> >(
142             map_pair) {}
143 };
144 
145 template <typename Derived, typename K, typename V,
146           WireFormatLite::FieldType key, WireFormatLite::FieldType value>
147 struct DeconstructMapEntry<MapEntry<Derived, K, V, key, value> > {
148   typedef K Key;
149   typedef V Value;
150   static constexpr WireFormatLite::FieldType kKeyFieldType = key;
151   static constexpr WireFormatLite::FieldType kValueFieldType = value;
152 };
153 
154 }  // namespace internal
155 }  // namespace protobuf
156 }  // namespace google
157 
158 #include <google/protobuf/port_undef.inc>
159 
160 #endif  // GOOGLE_PROTOBUF_MAP_ENTRY_H__
161