map_field_inl.h

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#ifndef GOOGLE_PROTOBUF_MAP_FIELD_INL_H__
#define GOOGLE_PROTOBUF_MAP_FIELD_INL_H__

#include <memory>

#include <google/protobuf/stubs/casts.h>
#include <google/protobuf/map.h>
#include <google/protobuf/map_field.h>
#include <google/protobuf/map_type_handler.h>

#ifdef SWIG
#error "You cannot SWIG proto headers"
#endif

namespace google {
namespace protobuf {
namespace internal {
// UnwrapMapKey template
template <typename T>
T UnwrapMapKey(const MapKey& map_key);
template <>
inline int32 UnwrapMapKey<int32>(const MapKey& map_key) {
  return map_key.GetInt32Value();
}
template <>
inline uint32 UnwrapMapKey<uint32>(const MapKey& map_key) {
  return map_key.GetUInt32Value();
}
template <>
inline int64 UnwrapMapKey<int64>(const MapKey& map_key) {
  return map_key.GetInt64Value();
}
template <>
inline uint64 UnwrapMapKey<uint64>(const MapKey& map_key) {
  return map_key.GetUInt64Value();
}
template <>
inline bool UnwrapMapKey<bool>(const MapKey& map_key) {
  return map_key.GetBoolValue();
}
template <>
inline std::string UnwrapMapKey<std::string>(const MapKey& map_key) {
  return map_key.GetStringValue();
}

// SetMapKey template
template <typename T>
inline void SetMapKey(MapKey* map_key, const T& value);
template <>
inline void SetMapKey<int32>(MapKey* map_key, const int32& value) {
  map_key->SetInt32Value(value);
}
template <>
inline void SetMapKey<uint32>(MapKey* map_key, const uint32& value) {
  map_key->SetUInt32Value(value);
}
template <>
inline void SetMapKey<int64>(MapKey* map_key, const int64& value) {
  map_key->SetInt64Value(value);
}
template <>
inline void SetMapKey<uint64>(MapKey* map_key, const uint64& value) {
  map_key->SetUInt64Value(value);
}
template <>
inline void SetMapKey<bool>(MapKey* map_key, const bool& value) {
  map_key->SetBoolValue(value);
}
template <>
inline void SetMapKey<std::string>(MapKey* map_key, const std::string& value) {
  map_key->SetStringValue(value);
}

// ------------------------TypeDefinedMapFieldBase---------------
template <typename Key, typename T>
typename Map<Key, T>::const_iterator&
TypeDefinedMapFieldBase<Key, T>::InternalGetIterator(
    const MapIterator* map_iter) const {
  return *reinterpret_cast<typename Map<Key, T>::const_iterator*>(
      map_iter->iter_);
}

template <typename Key, typename T>
void TypeDefinedMapFieldBase<Key, T>::MapBegin(MapIterator* map_iter) const {
  InternalGetIterator(map_iter) = GetMap().begin();
  SetMapIteratorValue(map_iter);
}

template <typename Key, typename T>
void TypeDefinedMapFieldBase<Key, T>::MapEnd(MapIterator* map_iter) const {
  InternalGetIterator(map_iter) = GetMap().end();
}

template <typename Key, typename T>
bool TypeDefinedMapFieldBase<Key, T>::EqualIterator(
    const MapIterator& a, const MapIterator& b) const {
  return InternalGetIterator(&a) == InternalGetIterator(&b);
}

template <typename Key, typename T>
void TypeDefinedMapFieldBase<Key, T>::IncreaseIterator(
    MapIterator* map_iter) const {
  ++InternalGetIterator(map_iter);
  SetMapIteratorValue(map_iter);
}

template <typename Key, typename T>
void TypeDefinedMapFieldBase<Key, T>::InitializeIterator(
    MapIterator* map_iter) const {
  map_iter->iter_ = new typename Map<Key, T>::const_iterator;
  GOOGLE_CHECK(map_iter->iter_ != NULL);
}

template <typename Key, typename T>
void TypeDefinedMapFieldBase<Key, T>::DeleteIterator(
    MapIterator* map_iter) const {
  delete reinterpret_cast<typename Map<Key, T>::const_iterator*>(
      map_iter->iter_);
}

template <typename Key, typename T>
void TypeDefinedMapFieldBase<Key, T>::CopyIterator(
    MapIterator* this_iter, const MapIterator& that_iter) const {
  InternalGetIterator(this_iter) = InternalGetIterator(&that_iter);
  this_iter->key_.SetType(that_iter.key_.type());
  // MapValueRef::type() fails when containing data is null. However, if
  // this_iter points to MapEnd, data can be null.
  this_iter->value_.SetType(
      static_cast<FieldDescriptor::CppType>(that_iter.value_.type_));
  SetMapIteratorValue(this_iter);
}

// ----------------------------------------------------------------------

template <typename Derived, typename Key, typename T,
          WireFormatLite::FieldType kKeyFieldType,
          WireFormatLite::FieldType kValueFieldType, int default_enum_value>
int MapField<Derived, Key, T, kKeyFieldType, kValueFieldType,
             default_enum_value>::size() const {
  MapFieldBase::SyncMapWithRepeatedField();
  return static_cast<int>(impl_.GetMap().size());
}

template <typename Derived, typename Key, typename T,
          WireFormatLite::FieldType kKeyFieldType,
          WireFormatLite::FieldType kValueFieldType, int default_enum_value>
void MapField<Derived, Key, T, kKeyFieldType, kValueFieldType,
              default_enum_value>::Clear() {
  if (this->MapFieldBase::repeated_field_ != nullptr) {
    RepeatedPtrField<EntryType>* repeated_field =
        reinterpret_cast<RepeatedPtrField<EntryType>*>(
            this->MapFieldBase::repeated_field_);
    repeated_field->Clear();
  }

  impl_.MutableMap()->clear();
  // Data in map and repeated field are both empty, but we can't set status
  // CLEAN. Because clear is a generated API, we cannot invalidate previous
  // reference to map.
  MapFieldBase::SetMapDirty();
}

template <typename Derived, typename Key, typename T,
          WireFormatLite::FieldType kKeyFieldType,
          WireFormatLite::FieldType kValueFieldType, int default_enum_value>
void MapField<Derived, Key, T, kKeyFieldType, kValueFieldType,
              default_enum_value>::SetMapIteratorValue(MapIterator* map_iter)
    const {
  const Map<Key, T>& map = impl_.GetMap();
  typename Map<Key, T>::const_iterator iter =
      TypeDefinedMapFieldBase<Key, T>::InternalGetIterator(map_iter);
  if (iter == map.end()) return;
  SetMapKey(&map_iter->key_, iter->first);
  map_iter->value_.SetValue(&iter->second);
}

template <typename Derived, typename Key, typename T,
          WireFormatLite::FieldType kKeyFieldType,
          WireFormatLite::FieldType kValueFieldType, int default_enum_value>
bool MapField<Derived, Key, T, kKeyFieldType, kValueFieldType,
              default_enum_value>::ContainsMapKey(const MapKey& map_key) const {
  const Map<Key, T>& map = impl_.GetMap();
  const Key& key = UnwrapMapKey<Key>(map_key);
  typename Map<Key, T>::const_iterator iter = map.find(key);
  return iter != map.end();
}

template <typename Derived, typename Key, typename T,
          WireFormatLite::FieldType kKeyFieldType,
          WireFormatLite::FieldType kValueFieldType, int default_enum_value>
bool MapField<Derived, Key, T, kKeyFieldType, kValueFieldType,
              default_enum_value>::InsertOrLookupMapValue(const MapKey& map_key,
                                                          MapValueRef* val) {
  // Always use mutable map because users may change the map value by
  // MapValueRef.
  Map<Key, T>* map = MutableMap();
  const Key& key = UnwrapMapKey<Key>(map_key);
  typename Map<Key, T>::iterator iter = map->find(key);
  if (map->end() == iter) {
    val->SetValue(&((*map)[key]));
    return true;
  }
  // Key is already in the map. Make sure (*map)[key] is not called.
  // [] may reorder the map and iterators.
  val->SetValue(&(iter->second));
  return false;
}

template <typename Derived, typename Key, typename T,
          WireFormatLite::FieldType kKeyFieldType,
          WireFormatLite::FieldType kValueFieldType, int default_enum_value>
bool MapField<Derived, Key, T, kKeyFieldType, kValueFieldType,
              default_enum_value>::DeleteMapValue(const MapKey& map_key) {
  const Key& key = UnwrapMapKey<Key>(map_key);
  return MutableMap()->erase(key);
}

template <typename Derived, typename Key, typename T,
          WireFormatLite::FieldType kKeyFieldType,
          WireFormatLite::FieldType kValueFieldType, int default_enum_value>
void MapField<Derived, Key, T, kKeyFieldType, kValueFieldType,
              default_enum_value>::MergeFrom(const MapFieldBase& other) {
  MapFieldBase::SyncMapWithRepeatedField();
  const MapField& other_field = static_cast<const MapField&>(other);
  other_field.SyncMapWithRepeatedField();
  impl_.MergeFrom(other_field.impl_);
  MapFieldBase::SetMapDirty();
}

template <typename Derived, typename Key, typename T,
          WireFormatLite::FieldType kKeyFieldType,
          WireFormatLite::FieldType kValueFieldType, int default_enum_value>
void MapField<Derived, Key, T, kKeyFieldType, kValueFieldType,
              default_enum_value>::Swap(MapFieldBase* other) {
  MapField* other_field = down_cast<MapField*>(other);
  std::swap(this->MapFieldBase::repeated_field_, other_field->repeated_field_);
  impl_.Swap(&other_field->impl_);
  // a relaxed swap of the atomic
  auto other_state = other_field->state_.load(std::memory_order_relaxed);
  auto this_state = this->MapFieldBase::state_.load(std::memory_order_relaxed);
  other_field->state_.store(this_state, std::memory_order_relaxed);
  this->MapFieldBase::state_.store(other_state, std::memory_order_relaxed);
}

template <typename Derived, typename Key, typename T,
          WireFormatLite::FieldType kKeyFieldType,
          WireFormatLite::FieldType kValueFieldType, int default_enum_value>
void MapField<Derived, Key, T, kKeyFieldType, kValueFieldType,
              default_enum_value>::SyncRepeatedFieldWithMapNoLock() const {
  if (this->MapFieldBase::repeated_field_ == NULL) {
    if (this->MapFieldBase::arena_ == NULL) {
      this->MapFieldBase::repeated_field_ = new RepeatedPtrField<Message>();
    } else {
      this->MapFieldBase::repeated_field_ =
          Arena::CreateMessage<RepeatedPtrField<Message> >(
              this->MapFieldBase::arena_);
    }
  }
  const Map<Key, T>& map = impl_.GetMap();
  RepeatedPtrField<EntryType>* repeated_field =
      reinterpret_cast<RepeatedPtrField<EntryType>*>(
          this->MapFieldBase::repeated_field_);

  repeated_field->Clear();

  // The only way we can get at this point is through reflection and the
  // only way we can get the reflection object is by having called GetReflection
  // on the encompassing field. So that type must have existed and hence we
  // know that this MapEntry default_type has also already been constructed.
  // So it's safe to just call internal_default_instance().
  const Message* default_entry = Derived::internal_default_instance();
  for (typename Map<Key, T>::const_iterator it = map.begin(); it != map.end();
       ++it) {
    EntryType* new_entry =
        down_cast<EntryType*>(default_entry->New(this->MapFieldBase::arena_));
    repeated_field->AddAllocated(new_entry);
    (*new_entry->mutable_key()) = it->first;
    (*new_entry->mutable_value()) = it->second;
  }
}

template <typename Derived, typename Key, typename T,
          WireFormatLite::FieldType kKeyFieldType,
          WireFormatLite::FieldType kValueFieldType, int default_enum_value>
void MapField<Derived, Key, T, kKeyFieldType, kValueFieldType,
              default_enum_value>::SyncMapWithRepeatedFieldNoLock() const {
  Map<Key, T>* map = const_cast<MapField*>(this)->impl_.MutableMap();
  RepeatedPtrField<EntryType>* repeated_field =
      reinterpret_cast<RepeatedPtrField<EntryType>*>(
          this->MapFieldBase::repeated_field_);
  GOOGLE_CHECK(this->MapFieldBase::repeated_field_ != NULL);
  map->clear();
  for (typename RepeatedPtrField<EntryType>::iterator it =
           repeated_field->begin();
       it != repeated_field->end(); ++it) {
    // Cast is needed because Map's api and internal storage is different when
    // value is enum. For enum, we cannot cast an int to enum. Thus, we have to
    // copy value. For other types, they have same exposed api type and internal
    // stored type. We should not introduce value copy for them. We achieve this
    // by casting to value for enum while casting to reference for other types.
    (*map)[it->key()] = static_cast<CastValueType>(it->value());
  }
}

template <typename Derived, typename Key, typename T,
          WireFormatLite::FieldType kKeyFieldType,
          WireFormatLite::FieldType kValueFieldType, int default_enum_value>
size_t MapField<Derived, Key, T, kKeyFieldType, kValueFieldType,
                default_enum_value>::SpaceUsedExcludingSelfNoLock() const {
  size_t size = 0;
  if (this->MapFieldBase::repeated_field_ != NULL) {
    size += this->MapFieldBase::repeated_field_->SpaceUsedExcludingSelfLong();
  }
  Map<Key, T>* map = const_cast<MapField*>(this)->impl_.MutableMap();
  size += sizeof(*map);
  for (typename Map<Key, T>::iterator it = map->begin(); it != map->end();
       ++it) {
    size += KeyTypeHandler::SpaceUsedInMapLong(it->first);
    size += ValueTypeHandler::SpaceUsedInMapLong(it->second);
  }
  return size;
}
}  // namespace internal
}  // namespace protobuf
}  // namespace google

#endif  // GOOGLE_PROTOBUF_MAP_FIELD_INL_H__