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Differential D4501 Diff 14697 extern/draco/dracoenc/src/draco/metadata/metadata.h

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extern/draco/dracoenc/src/draco/metadata/metadata.h

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// Copyright 2017 The Draco Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#ifndef DRACO_METADATA_METADATA_H_
#define DRACO_METADATA_METADATA_H_
#include <cstring>
#include <memory>
#include <string>
#include <unordered_map>
#include <vector>
#include "draco/core/hash_utils.h"
namespace draco {
// Class for storing a value of an entry in Metadata. Internally it is
// represented by a buffer of data. It can be accessed by various data types,
// e.g. int, float, binary data or string.
class EntryValue {
public:
template <typename DataTypeT>
explicit EntryValue(const DataTypeT &data) {
const size_t data_type_size = sizeof(DataTypeT);
data_.resize(data_type_size);
memcpy(&data_[0], &data, data_type_size);
}
template <typename DataTypeT>
explicit EntryValue(const std::vector<DataTypeT> &data) {
const size_t total_size = sizeof(DataTypeT) * data.size();
data_.resize(total_size);
memcpy(&data_[0], &data[0], total_size);
}
EntryValue(const EntryValue &value);
explicit EntryValue(const std::string &value);
template <typename DataTypeT>
bool GetValue(DataTypeT *value) const {
const size_t data_type_size = sizeof(DataTypeT);
if (data_type_size != data_.size()) {
return false;
}
memcpy(value, &data_[0], data_type_size);
return true;
}
template <typename DataTypeT>
bool GetValue(std::vector<DataTypeT> *value) const {
if (data_.empty())
return false;
const size_t data_type_size = sizeof(DataTypeT);
if (data_.size() % data_type_size != 0) {
return false;
}
value->resize(data_.size() / data_type_size);
memcpy(&value->at(0), &data_[0], data_.size());
return true;
}
const std::vector<uint8_t> &data() const { return data_; }
private:
std::vector<uint8_t> data_;
friend struct EntryValueHasher;
};
// Functor for computing a hash from data stored within an EntryValue.
struct EntryValueHasher {
size_t operator()(const EntryValue &ev) const {
size_t hash = ev.data_.size();
for (int i = 0; i < ev.data_.size(); ++i) {
hash = HashCombine(ev.data_[i], hash);
}
return hash;
}
};
// Class for holding generic metadata. It has a list of entries which consist of
// an entry name and an entry value. Each Metadata could also have nested
// metadata.
class Metadata {
public:
Metadata() {}
Metadata(const Metadata &metadata);
// In theory, we support all types of data as long as it could be serialized
// to binary data. We provide the following functions for inserting and
// accessing entries of common data types. For now, developers need to know
// the type of entries they are requesting.
void AddEntryInt(const std::string &name, int32_t value);
bool GetEntryInt(const std::string &name, int32_t *value) const;
void AddEntryIntArray(const std::string &name,
const std::vector<int32_t> &value);
bool GetEntryIntArray(const std::string &name,
std::vector<int32_t> *value) const;
void AddEntryDouble(const std::string &name, double value);
bool GetEntryDouble(const std::string &name, double *value) const;
void AddEntryDoubleArray(const std::string &name,
const std::vector<double> &value);
bool GetEntryDoubleArray(const std::string &name,
std::vector<double> *value) const;
void AddEntryString(const std::string &name, const std::string &value);
bool GetEntryString(const std::string &name, std::string *value) const;
// Add a blob of data as an entry.
void AddEntryBinary(const std::string &name,
const std::vector<uint8_t> &value);
bool GetEntryBinary(const std::string &name,
std::vector<uint8_t> *value) const;
bool AddSubMetadata(const std::string &name,
std::unique_ptr<Metadata> sub_metadata);
const Metadata *GetSubMetadata(const std::string &name) const;
void RemoveEntry(const std::string &name);
int num_entries() const { return static_cast<int>(entries_.size()); }
const std::unordered_map<std::string, EntryValue> &entries() const {
return entries_;
}
const std::unordered_map<std::string, std::unique_ptr<Metadata>>
&sub_metadatas() const {
return sub_metadatas_;
}
private:
// Make this function private to avoid adding undefined data types.
template <typename DataTypeT>
void AddEntry(const std::string &entry_name, const DataTypeT &entry_value) {
const auto itr = entries_.find(entry_name);
if (itr != entries_.end())
entries_.erase(itr);
entries_.insert(std::make_pair(entry_name, EntryValue(entry_value)));
}
// Make this function private to avoid adding undefined data types.
template <typename DataTypeT>
bool GetEntry(const std::string &entry_name, DataTypeT *entry_value) const {
const auto itr = entries_.find(entry_name);
if (itr == entries_.end()) {
return false;
}
return itr->second.GetValue(entry_value);
}
std::unordered_map<std::string, EntryValue> entries_;
std::unordered_map<std::string, std::unique_ptr<Metadata>> sub_metadatas_;
friend struct MetadataHasher;
};
// Functor for computing a hash from data stored within a metadata class.
struct MetadataHasher {
size_t operator()(const Metadata &metadata) const {
size_t hash =
HashCombine(metadata.entries_.size(), metadata.sub_metadatas_.size());
EntryValueHasher entry_value_hasher;
for (const auto &entry : metadata.entries_) {
hash = HashCombine(entry.first, hash);
hash = HashCombine(entry_value_hasher(entry.second), hash);
}
MetadataHasher metadata_hasher;
for (auto &&sub_metadata : metadata.sub_metadatas_) {
hash = HashCombine(sub_metadata.first, hash);
hash = HashCombine(metadata_hasher(*sub_metadata.second), hash);
}
return hash;
}
};
} // namespace draco
#endif // DRACO_METADATA_METADATA_H_