WeChatHelper/protobuf/google/protobuf/reflection_internal.h
2024-06-11 08:43:45 +08:00

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// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc. All rights reserved.
// https://developers.google.com/protocol-buffers/
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#ifndef GOOGLE_PROTOBUF_REFLECTION_INTERNAL_H__
#define GOOGLE_PROTOBUF_REFLECTION_INTERNAL_H__
#include <google/protobuf/map_field.h>
#include <google/protobuf/reflection.h>
#include <google/protobuf/repeated_field.h>
namespace google {
namespace protobuf {
namespace internal {
// A base class for RepeatedFieldAccessor implementations that can support
// random-access efficiently. All iterator methods delegates the work to
// corresponding random-access methods.
class RandomAccessRepeatedFieldAccessor : public RepeatedFieldAccessor {
public:
virtual ~RandomAccessRepeatedFieldAccessor() {}
virtual Iterator* BeginIterator(const Field* data) const {
return PositionToIterator(0);
}
virtual Iterator* EndIterator(const Field* data) const {
return PositionToIterator(this->Size(data));
}
virtual Iterator* CopyIterator(const Field* data,
const Iterator* iterator) const {
return const_cast<Iterator*>(iterator);
}
virtual Iterator* AdvanceIterator(const Field* data,
Iterator* iterator) const {
return PositionToIterator(IteratorToPosition(iterator) + 1);
}
virtual bool EqualsIterator(const Field* data,
const Iterator* a,
const Iterator* b) const {
return a == b;
}
virtual void DeleteIterator(const Field* data, Iterator* iterator) const {
}
virtual const Value* GetIteratorValue(const Field* data,
const Iterator* iterator,
Value* scratch_space) const {
return Get(data, static_cast<int>(IteratorToPosition(iterator)),
scratch_space);
}
private:
static intptr_t IteratorToPosition(const Iterator* iterator) {
return reinterpret_cast<intptr_t>(iterator);
}
static Iterator* PositionToIterator(intptr_t position) {
return reinterpret_cast<Iterator*>(position);
}
};
// Base class for RepeatedFieldAccessor implementations that manipulates
// RepeatedField<T>.
template<typename T>
class RepeatedFieldWrapper : public RandomAccessRepeatedFieldAccessor {
public:
RepeatedFieldWrapper() {}
virtual ~RepeatedFieldWrapper() {}
virtual bool IsEmpty(const Field* data) const {
return GetRepeatedField(data)->empty();
}
virtual int Size(const Field* data) const {
return GetRepeatedField(data)->size();
}
virtual const Value* Get(const Field* data, int index,
Value* scratch_space) const {
return ConvertFromT(GetRepeatedField(data)->Get(index), scratch_space);
}
virtual void Clear(Field* data) const {
MutableRepeatedField(data)->Clear();
}
virtual void Set(Field* data, int index, const Value* value) const {
MutableRepeatedField(data)->Set(index, ConvertToT(value));
}
virtual void Add(Field* data, const Value* value) const {
MutableRepeatedField(data)->Add(ConvertToT(value));
}
virtual void RemoveLast(Field* data) const {
MutableRepeatedField(data)->RemoveLast();
}
virtual void SwapElements(Field* data, int index1, int index2) const {
MutableRepeatedField(data)->SwapElements(index1, index2);
}
protected:
typedef RepeatedField<T> RepeatedFieldType;
static const RepeatedFieldType* GetRepeatedField(const Field* data) {
return reinterpret_cast<const RepeatedFieldType*>(data);
}
static RepeatedFieldType* MutableRepeatedField(Field* data) {
return reinterpret_cast<RepeatedFieldType*>(data);
}
// Convert an object recevied by this accessor to an object to be stored in
// the underlying RepeatedField.
virtual T ConvertToT(const Value* value) const = 0;
// Convert an object stored in RepeatedPtrField to an object that will be
// returned by this accessor. If the two objects have the same type (true
// for string fields with ctype=STRING), a pointer to the source object can
// be returned directly. Otherwise, data should be copied from value to
// scratch_space and scratch_space should be returned.
virtual const Value* ConvertFromT(const T& value,
Value* scratch_space) const = 0;
};
// Base class for RepeatedFieldAccessor implementations that manipulates
// RepeatedPtrField<T>.
template<typename T>
class RepeatedPtrFieldWrapper : public RandomAccessRepeatedFieldAccessor {
public:
RepeatedPtrFieldWrapper() {}
virtual ~RepeatedPtrFieldWrapper() {}
virtual bool IsEmpty(const Field* data) const {
return GetRepeatedField(data)->empty();
}
virtual int Size(const Field* data) const {
return GetRepeatedField(data)->size();
}
virtual const Value* Get(const Field* data, int index,
Value* scratch_space) const {
return ConvertFromT(GetRepeatedField(data)->Get(index), scratch_space);
}
virtual void Clear(Field* data) const {
MutableRepeatedField(data)->Clear();
}
virtual void Set(Field* data, int index, const Value* value) const {
ConvertToT(value, MutableRepeatedField(data)->Mutable(index));
}
virtual void Add(Field* data, const Value* value) const {
T* allocated = New(value);
ConvertToT(value, allocated);
MutableRepeatedField(data)->AddAllocated(allocated);
}
virtual void RemoveLast(Field* data) const {
MutableRepeatedField(data)->RemoveLast();
}
virtual void SwapElements(Field* data, int index1, int index2) const {
MutableRepeatedField(data)->SwapElements(index1, index2);
}
protected:
typedef RepeatedPtrField<T> RepeatedFieldType;
static const RepeatedFieldType* GetRepeatedField(const Field* data) {
return reinterpret_cast<const RepeatedFieldType*>(data);
}
static RepeatedFieldType* MutableRepeatedField(Field* data) {
return reinterpret_cast<RepeatedFieldType*>(data);
}
// Create a new T instance. For repeated message fields, T can be specified
// as google::protobuf::Message so we can't use "new T()" directly. In that case, value
// should be a message of the same type (it's ensured by the caller) and a
// new message object will be created using it.
virtual T* New(const Value* value) const = 0;
// Convert an object received by this accessor to an object that will be
// stored in the underlying RepeatedPtrField.
virtual void ConvertToT(const Value* value, T* result) const = 0;
// Convert an object stored in RepeatedPtrField to an object that will be
// returned by this accessor. If the two objects have the same type (true
// for string fields with ctype=STRING), a pointer to the source object can
// be returned directly. Otherwise, data should be copied from value to
// scratch_space and scratch_space should be returned.
virtual const Value* ConvertFromT(const T& value,
Value* scratch_space) const = 0;
};
// An implementation of RandomAccessRepeatedFieldAccessor that manipulates
// MapFieldBase.
class MapFieldAccessor : public RandomAccessRepeatedFieldAccessor {
public:
MapFieldAccessor() {}
virtual ~MapFieldAccessor() {}
virtual bool IsEmpty(const Field* data) const {
return GetRepeatedField(data)->empty();
}
virtual int Size(const Field* data) const {
return GetRepeatedField(data)->size();
}
virtual const Value* Get(const Field* data, int index,
Value* scratch_space) const {
return ConvertFromEntry(GetRepeatedField(data)->Get(index), scratch_space);
}
virtual void Clear(Field* data) const {
MutableRepeatedField(data)->Clear();
}
virtual void Set(Field* data, int index, const Value* value) const {
ConvertToEntry(value, MutableRepeatedField(data)->Mutable(index));
}
virtual void Add(Field* data, const Value* value) const {
Message* allocated = New(value);
ConvertToEntry(value, allocated);
MutableRepeatedField(data)->AddAllocated(allocated);
}
virtual void RemoveLast(Field* data) const {
MutableRepeatedField(data)->RemoveLast();
}
virtual void SwapElements(Field* data, int index1, int index2) const {
MutableRepeatedField(data)->SwapElements(index1, index2);
}
virtual void Swap(
Field* data,
const internal::RepeatedFieldAccessor* other_mutator,
Field* other_data) const {
GOOGLE_CHECK(this == other_mutator);
MutableRepeatedField(data)->Swap(MutableRepeatedField(other_data));
}
protected:
typedef RepeatedPtrField<Message> RepeatedFieldType;
static const RepeatedFieldType* GetRepeatedField(const Field* data) {
return reinterpret_cast<const RepeatedFieldType*>(
(&reinterpret_cast<const MapFieldBase*>(data)->GetRepeatedField()));
}
static RepeatedFieldType* MutableRepeatedField(Field* data) {
return reinterpret_cast<RepeatedFieldType*>(
reinterpret_cast<MapFieldBase*>(data)->MutableRepeatedField());
}
virtual Message* New(const Value* value) const {
return static_cast<const Message*>(value)->New();
}
// Convert an object received by this accessor to an MapEntry message to be
// stored in the underlying MapFieldBase.
virtual void ConvertToEntry(const Value* value, Message* result) const {
result->CopyFrom(*static_cast<const Message*>(value));
}
// Convert a MapEntry message stored in the underlying MapFieldBase to an
// object that will be returned by this accessor.
virtual const Value* ConvertFromEntry(const Message& value,
Value* scratch_space) const {
return static_cast<const Value*>(&value);
}
};
// Default implementations of RepeatedFieldAccessor for primitive types.
template<typename T>
class RepeatedFieldPrimitiveAccessor : public RepeatedFieldWrapper<T> {
typedef void Field;
typedef void Value;
using RepeatedFieldWrapper<T>::MutableRepeatedField;
public:
RepeatedFieldPrimitiveAccessor() {}
virtual ~RepeatedFieldPrimitiveAccessor() {}
virtual void Swap(
Field* data,
const internal::RepeatedFieldAccessor* other_mutator,
Field* other_data) const {
// Currently RepeatedFieldPrimitiveAccessor is the only implementation of
// RepeatedFieldAccessor for primitive types. As we are using singletons
// for these accessors, here "other_mutator" must be "this".
GOOGLE_CHECK(this == other_mutator);
MutableRepeatedField(data)->Swap(MutableRepeatedField(other_data));
}
protected:
virtual T ConvertToT(const Value* value) const {
return *static_cast<const T*>(value);
}
virtual const Value* ConvertFromT(const T& value,
Value* scratch_space) const {
return static_cast<const Value*>(&value);
}
};
// Default implementation of RepeatedFieldAccessor for string fields with
// ctype=STRING.
class RepeatedPtrFieldStringAccessor : public RepeatedPtrFieldWrapper<string> {
typedef void Field;
typedef void Value;
using RepeatedFieldAccessor::Add;
public:
RepeatedPtrFieldStringAccessor() {}
virtual ~RepeatedPtrFieldStringAccessor() {}
virtual void Swap(
Field* data,
const internal::RepeatedFieldAccessor* other_mutator,
Field* other_data) const {
if (this == other_mutator) {
MutableRepeatedField(data)->Swap(MutableRepeatedField(other_data));
} else {
RepeatedPtrField<string> tmp;
tmp.Swap(MutableRepeatedField(data));
int other_size = other_mutator->Size(other_data);
for (int i = 0; i < other_size; ++i) {
Add<string>(data, other_mutator->Get<string>(other_data, i));
}
int size = Size(data);
other_mutator->Clear(other_data);
for (int i = 0; i < size; ++i) {
other_mutator->Add<string>(other_data, tmp.Get(i));
}
}
}
protected:
virtual string* New(const Value*) const {
return new string();
}
virtual void ConvertToT(const Value* value, string* result) const {
*result = *static_cast<const string*>(value);
}
virtual const Value* ConvertFromT(const string& value,
Value* scratch_space) const {
return static_cast<const Value*>(&value);
}
};
class RepeatedPtrFieldMessageAccessor
: public RepeatedPtrFieldWrapper<Message> {
typedef void Field;
typedef void Value;
public:
RepeatedPtrFieldMessageAccessor() {}
virtual ~RepeatedPtrFieldMessageAccessor() {}
virtual void Swap(
Field* data,
const internal::RepeatedFieldAccessor* other_mutator,
Field* other_data) const {
GOOGLE_CHECK(this == other_mutator);
MutableRepeatedField(data)->Swap(MutableRepeatedField(other_data));
}
protected:
virtual Message* New(const Value* value) const {
return static_cast<const Message*>(value)->New();
}
virtual void ConvertToT(const Value* value, Message* result) const {
result->CopyFrom(*static_cast<const Message*>(value));
}
virtual const Value* ConvertFromT(const Message& value,
Value* scratch_space) const {
return static_cast<const Value*>(&value);
}
};
} // namespace internal
} // namespace protobuf
} // namespace google
#endif // GOOGLE_PROTOBUF_REFLECTION_INTERNAL_H__