mirror of
https://github.com/ton-blockchain/ton
synced 2025-03-09 15:40:10 +00:00
87 lines
2.2 KiB
C++
87 lines
2.2 KiB
C++
/*
|
|
This file is part of TON Blockchain Library.
|
|
|
|
TON Blockchain Library is free software: you can redistribute it and/or modify
|
|
it under the terms of the GNU Lesser General Public License as published by
|
|
the Free Software Foundation, either version 2 of the License, or
|
|
(at your option) any later version.
|
|
|
|
TON Blockchain Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public License
|
|
along with TON Blockchain Library. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
Copyright 2017-2019 Telegram Systems LLP
|
|
*/
|
|
#pragma once
|
|
|
|
#include "td/utils/common.h"
|
|
|
|
#if TD_HAVE_ABSL
|
|
#include <absl/hash/hash.h>
|
|
#endif
|
|
|
|
#include <utility>
|
|
|
|
namespace td {
|
|
// A simple wrapper for absl::flat_hash_map, std::unordered_map and probably some our implementaion of hash map in
|
|
// the future
|
|
|
|
// We will introduce out own Hashing utility like an absl one.
|
|
class Hasher {
|
|
public:
|
|
Hasher() = default;
|
|
explicit Hasher(size_t init_value) : hash_(init_value) {
|
|
}
|
|
std::size_t finalize() const {
|
|
return hash_;
|
|
}
|
|
|
|
static Hasher combine(Hasher hasher, size_t value) {
|
|
hasher.hash_ ^= value;
|
|
return hasher;
|
|
}
|
|
|
|
template <class A, class B>
|
|
static Hasher combine(Hasher hasher, const std::pair<A, B> &value) {
|
|
hasher = AbslHashValue(std::move(hasher), value.first);
|
|
hasher = AbslHashValue(std::move(hasher), value.second);
|
|
return hasher;
|
|
}
|
|
|
|
private:
|
|
std::size_t hash_{0};
|
|
};
|
|
|
|
template <class IgnoreT>
|
|
class TdHash {
|
|
public:
|
|
template <class T>
|
|
std::size_t operator()(const T &value) const noexcept {
|
|
return AbslHashValue(Hasher(), value).finalize();
|
|
}
|
|
};
|
|
|
|
#if TD_HAVE_ABSL
|
|
template <class T>
|
|
using AbslHash = absl::Hash<T>;
|
|
#endif
|
|
|
|
// default hash implementations
|
|
template <class H, class T>
|
|
decltype(H::combine(std::declval<H>(), std::declval<T>())) AbslHashValue(H hasher, const T &value) {
|
|
return H::combine(std::move(hasher), value);
|
|
}
|
|
|
|
#if TD_HAVE_ABSL
|
|
template <class T>
|
|
using Hash = AbslHash<T>;
|
|
#else
|
|
template <class T>
|
|
using Hash = TdHash<T>;
|
|
#endif
|
|
|
|
} // namespace td
|