yalantinglibs/include/ylt/struct_pb.hpp

103 lines
3.5 KiB
C++

/*
* Copyright (c) 2023, Alibaba Group Holding Limited;
*
* 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.
*/
#pragma once
#include <cassert>
#include <cstdint>
#include <cstring>
#include <vector>
#if defined __clang__
#define STRUCT_PB_INLINE __attribute__((always_inline)) inline
#elif defined _MSC_VER
#define STRUCT_PB_INLINE __forceinline
#else
#define STRUCT_PB_INLINE __attribute__((always_inline)) inline
#endif
#define STRUCT_PB_NODISCARD [[nodiscard]]
namespace struct_pb {
struct UnknownFields {
STRUCT_PB_NODISCARD std::size_t total_size() const {
std::size_t total = 0;
for (const auto& f : fields) {
total += f.len;
}
return total;
}
void serialize_to(char* data, std::size_t& pos, std::size_t size) const {
for (const auto& f : fields) {
assert(pos + f.len <= size);
std::memcpy(data + pos, f.data, f.len);
pos += f.len;
}
}
void add_field(const char* data, std::size_t start, std::size_t end) {
fields.push_back(Field{data + start, end - start});
}
struct Field {
const char* data;
std::size_t len;
};
std::vector<Field> fields;
};
/*
* Low-Level API for struct_pb user
* the following internal API will be generated by struct_pb protoc plugin
*/
namespace internal {
template <typename T>
STRUCT_PB_NODISCARD std::size_t get_needed_size(
const T& t, const UnknownFields& unknown_fields = {});
template <typename T>
void serialize_to(char* data, std::size_t size, const T& t,
const UnknownFields& unknown_fields = {});
template <typename T>
STRUCT_PB_NODISCARD bool deserialize_to(T& t, const char* data,
std::size_t size,
UnknownFields& unknown_fields);
template <typename T>
STRUCT_PB_NODISCARD bool deserialize_to(T& t, const char* data,
std::size_t size);
} // namespace internal
/*
* High-Level API for struct_pb user
* If you need more fine-grained operations, encapsulate the internal API
* yourself.
*/
template <typename Buffer = std::vector<char>, typename T>
STRUCT_PB_NODISCARD Buffer serialize(const T& t,
const UnknownFields& unknown_fields = {}) {
Buffer buffer;
auto size = struct_pb::internal::get_needed_size(t, unknown_fields);
buffer.resize(size);
struct_pb::internal::serialize_to(buffer.data(), buffer.size(), t,
unknown_fields);
return buffer;
}
template <typename T, typename Buffer>
STRUCT_PB_NODISCARD STRUCT_PB_INLINE bool deserialize_to(
T& t, UnknownFields& unknown_fields, const Buffer& buffer) {
return struct_pb::internal::deserialize_to(t, buffer.data(), buffer.size(),
unknown_fields);
}
template <typename T, typename Buffer>
STRUCT_PB_NODISCARD STRUCT_PB_INLINE bool deserialize_to(T& t,
const Buffer& buffer) {
return struct_pb::internal::deserialize_to(t, buffer.data(), buffer.size());
}
} // namespace struct_pb